I think that in our western culture it is a combination of both LBR and LBD. I mean we go to school for years reading and practicing things we have read.
In way, way, way back times it was probably more LBD. I would imagine someone learned how to do something by someone who knew how to do it showing them
and then they would practice it until they got good at it. Probably why we still are not 100% up on how they built the pyramids. They didn't write down the damned instructions
so that means it must have been passed on by someone showing them (I don't mean aliens)
Anyway it's a game. I play it as is. That is all.
Oh I forgot to mention, trader rekt is an ass.
Well, you don't learn tennis by reading a magazine and you don't become better at it by reading more magazines.
Other than quality levels of something, the game does not represent any aspect of getting better at crafting things. So practice (LBD) isn't reflected in the game. You could say that LBD makes sense for quality levels. In that one area of crafting, you could realistically get better by practice (by doing). However, practicing to make iron doesn't make you good at making steel. Practicing making a bow doesn't make you good at making a crossbow. If you have no schematics or anything to teach you how to make those things, then learning such things would require so much time and effort as to not fit within a reasonable timeframe within a game. Take someone who has never made a pistol and ask them to learn how to make one by trial and error (LBD). It won't happen. Yes, people did come up with these designs in the past through trial and error but that process took considerable time and energy. It wasn't done in the middle of hunting and scavenging and trying to defend against zombies every day with hordes attacking every week. And even if it did happen that way, it wasn't done within days or weeks or even months. Other than food recipes or clothing, pretty much anything crafted in the game required many years of study and research and learning techniques from others that are then adjusted to create a different design that wasn't known previously. And even then, as I said, it's using information learned from others. You are a character who presumably isn't an expert at all these different crafts. You can't just practice your way into making something complex without prior knowledge or learning through reading or being taught. Few people here could create a working pistol, shotgun, drone, vehicle, etc. through trial and error. Your character isn't any different. As I said, other than quality levels, crafting isn't about getting better through practice. It's about learning new things that you did not previously know. That doesn't happen just by doing.
Now... if you're talking about quality levels, then I agree that your ability to make better quality levels could come through LBD. However, that means grinding like what they had previously and what is seen in basically any LBD game out there where LBD is used in crafting. You have to craft a ton of stuff just to get better so you can make better things that you have to then craft more of to make even better things within the same tier. Yes, that is realistic but it isn't great for gameplay for a lot of people. Some people love that kind of grinding but many do not. I can't say which side has the greater number of people on it and I doubt anyone can. We can guess but that doesn't mean we are correct. And in either case, there will be a lot of people on both sides, so it doesn't even matter because it's all just opinion about whether it's fun or not. And that still only covers quality levels and not tiers or new items.
Some things may be easy to make or not require much effort to figure out how to make. I could craft a simple workbench easily, for example. I wouldn't need to learn how. Granted, it wouldn't be great quality, but it would be functional. But other things are far more complicated and require being taught or learning by reading/research into how to do the thing. And in terms of gameplay, having all crafting follow the same mechanics is better than having some things use one mechanic and some things use another just because some items are easy enough to figure out how to craft without having been taught to do so.
So, in terms of crafting, LBR makes the most sense and is entirely realistic and provides good gameplay. If you want to discuss other things in the game like fighting skills, that most definitely is improved through practice. And that is actually how the game works. You gain experience by doing. It isn't separated into different skills and is only an overall experience but it's still experience gained through doing things in the game. That experience is then used to get better at different things through the use of perks. So you are use LBD to gain ability in fighting skills. It is a bit abstracted as it is in many games rather than being tied to specific skills like you might see in some games like the Elder Scrolls games but it's still LBD. Maybe you prefer Elder Scrolls games where if you run, you gain skill in running and if you swing a sword, you gain skill in swinging a sword. That's fine but that's not the only way to create a game. Most games with skills have you gain experience and that experience can be used to improve your skills. That might be through perks or a skill tree (or both, like in Fallout) or it could be through an automatic system where all skills simply get better each time you level up. These are all ways of using LBD in a game.
LBD simply doesn't work well for crafting. LBR simply doesn't work well for fighting skills (though it can work for learning a new type of fighting skill). A hybrid of LBD and LBR is the better option for games that have both fighting and crafting skills. And we have that here. It may not be designed all that well and is certainly nowhere close to being balanced but it is there. Some games offer the third option of "LTBT" (Learn Through Being Taught - sorry, I can't think of a 3 letter acronym and Learn By Teaching sounds like you're doing the teaching instead of being taught, which isn't the same thing). This is usually done through a master of some sort that you pay to unlock a skill or improve a skill. It is sometimes the only way to gain a new skill or level of skill but in most cases, it is just an alternative and faster way to learn or improve a skill. They could add something like that to this game but I don't really see any need for it.
People learn things in real life through a combination of LBR, LBD, and "LTBT". But not everything can be learned by only one of these methods. Some things require more than one method to really learn it. And some may require all 3 to really get good at it. If you have knowledge of the way people learn in school, you'll know that some people learn better from one method than from other methods. Some learn best by having someone explain it to them. Others learn best by hands on. Others learn best by reading. But even in those cases, it depends on what you're learning as to what method(s) are necessary to learn the skill.
One other thing to consider... yes, I could pick up a stick (club) and start swinging it around and with practice, I would probably get relatively good at hitting zombies with it. But without anyone to teach me good technique or reading something that explains good technique, the chances I'll get to be a master with a club would be very low. Pit me against someone who was taught how to use it and even if I spent years practicing, I probably wouldn't stand a chance. LBD can only get you so far on its own.