I see that there are tons of players all around, that is complaining in one way or the other, about performance issues, especially FPS dropping like a stone in water.
As a dedicated PC gamer over the past 20+ years, with nearly 7k hours in 7DTD, and up untill a year ago, my specs were i5 4500 series CPU, 960 Ti OC 2GB GfX and 16 GB DDR4, I had spent most of my time, struggling with getting anywhere near an average 40 fps. Last year, I upgraded to a Ryzen 7 5700G (integrated graphics) and 64 GB GDDR6 ram. gave me a better FPS amount, but it was still with the low settings enabled. Added a 3060 OC 12 GB GDDR GPU last week, and now it runs almost perfectly, only way to drop below 60 fps, is 36 player planted trees.
So, these are the things that I over the years, have found to really screw with your frames, in decending order.
Trees
blocks
terrain altering
excessive amount of zombies
cop spit (since V1 was released, and still gives my GPU some problems).
Now, after plugging in my new GfX, everything went ultra+, so I had some minor issues. dropped to ultra, and raised FPS to 90+ everywhere, except around a bunch of trees.
So, my advice is as follows.
Dont put 2 million blocks in an area, and dont build both main base and horde base in the same location. Keep HB to something simple. small "staired" compound or a "cage above pit" base.
Keep trees nearby, but far enough away, so they dont load visually. and if you really have to plant them next to your base, looking in their direction, will kill your FPS, so consider yourself warned. My old machine was pulling out a .45 to commit suicide, every time I was looking at 20 player planted trees. the new "only" one requires 36 trees, before it gets suicidal.
keep zombies to what the game suggests, or a tad lower than that. especially, if you are hosting a game on a console. the suggestions are there, based on single player, not you and your 3 buddies having 8 zombies each, totalling 32 zombies at all times, during blood moon. 20 should be absolute max, so 5 per player, shold be efficient, and still fun.
Oh, and try to kill cops, before they puke all over the place. a good weapon is M60 orsomething else with a large magasine with rad, drum, x2/x4 scope (easier to see in the distance) and bipod (for better handling of the M60). In that order.
And this one is for the game developers. Whomever decided that the game should have motion blur...??? I hope your ass itches and your arms are too short.....