Is there a need? No. Is there a want? Yes. A backpack could potentially be found or crafted earlier in the game, before the player has access to the 4x4 Truck, Gyro, or Drone. The new storage mods are also as dependent on RNG as finding a backpack would be, or perhaps a backpack would be an earlier Loot Stage item until better options are "unlocked." Some of my friends that play do not like the drone for a variety of reasons, but they have said that they would be happy to wear a backpack to add a row or so of storage slots. Yes, we can and do drop a crate and pick stuff up later, but that takes time that could be better served doing something else, or you could forget that you left some loot at a POI somewhere.
Unless they change it (they probably will), the storage mod schematics drop constantly right now. They are as bad as the vehicle headlight mod schematics. The way it is now, it drops so much that you'd have to have the worst possible RNG ever to not get them early in the game if you're doing even a medium amount of looting. And if you're not looting much, you don't need them anyhow. If you haven't found one by the time you get a bicycle, that would be very unusual. Unless perhaps if you set loot to 25%.
In any case, we did just fine before those schematics, so they are certainly not critical to the game. Not only that, but we also got free slots in all vehicles even without the mods, so we're already better off than we used to be. Add in that backpacks, if added, would also be RNG - either requiring schematics that you'd have to find (no different from the vehicle storage mod schematics) or backpacks you'd have to find (still RNG). So it wouldn't be much change in the end as far as RNG goes.
And as far as timing, you get a bicycle really early. With 2 storage mod schematics, you have 30 slots in the bicycle. That, combined with your inventory, is a lot. Considering you are not likely to be doing much very far from your base before you have decent transportation, placing a crate to store stuff and then picking it up once you have a decent vehicle isn't really a problem since it would be very quick to bring it back to base later. It really doesn't take much time to do that. Use drop all to fill it and pick out anything you need right away, or pick what to put into it. Then leave it on the road where it's easy to find. You'll be close to home, so you're going to be seeing it in the road regularly and aren't likely to forget it. Once you have a decent vehicle, like a motorcycle, you can drop your storage mods onto that, drive to the crate, which shouldn't take very long since you aren't likely to have been too far from home before having a decent vehicle, use take all to fill your inventory, turn to your motorcycle and use drop all, then turn back to the crate and take all again. Repeat as needed, though it'll only take a few times at most to get everything out of a crate. Then drive back to base and unload. Unloading at the base isn't any extra time because you'd have to unload either way. So it really isn't much time at all to do that if you need to.
And, in the end, you do not need to take every single thing you find. You'll use most things, but most are only used in limited amounts. If you're not crafting shotgun shells, your use of paper will be very limited. Once you have a couple hundred, you really don't need to gather more if you're not making shotgun shells. Pipes are used for a variety of things, but you still normally aren't using a ton of them, and they are easy to get if you happen to need them and are short. So you don't really have to grab them all the time if you're short on space. Things like paint brushes or wire tools or flashlights are all things that you only really need one or two in most cases and the rest can be ignored. Those are just a few examples. Yes, things can be sold for money, and some can be scrapped for resources or smelted. But if you don't need money, it's not critical to gather everything. And unless you're regularly buying stuff, money isn't really needed for much in this game. I might occasionally buy a magazine or book, but only if I really need something. I might consider buying a drone if I'm way too far away on magazines to craft one. I'll buy the mods for the dew collector. And if I do solar, I'll buy those. It's not common for me to buy much more than that. I know others spend a ton at the trader, but even then, you can make a lot of money quickly and easily if you focus on good ways to make money. So not picking up a dozen pipes or whatever and losing out on 100 dukes or whatever they might sell for isn't going to break your game.
I get the interest in not having to think about inventory and just take every single thing you find, but why even bother having an inventory if you can carry as much as you want? We're close to that already.
If they did anything, then maybe something specific to the drone. Maybe tell it to sell everything in the inventory to the trader and it would leave and return. Or perhaps tell it to drop everything into your storage at your base (probably needing to set a specific crate to use as a dump crate for it) and it would leave to drop stuff off and then return. That doesn't help in the early game, but you aren't looting as much in a tier 1 POI as you are in a tier 5 POI, so your amount of loot is much more limited in the early game anyhow.
To a degree, if mods can do it, then it could be implemented into the vanilla game. Again, to a degree. I think this idea is within the degree.
