I would say the only ammo you can actually have too much of would be .22lr
That’s of course subjective based on much you shoot but it just has a much shorter shelf life than center fire ammo.
I’m sure we all have and shoot surplus from the 40’s, and all of mine still works like a charm
But rimfire bullets start to oxidize and get funky much quicker it seems
I hadn’t noticed that about 22 shells if stored properly. I’ve got plenty from the 70’s and 80’s that still shoot fine. I picked up 100,000 rds for Y2K that are still fine.