There is a free to play game Armored Warfare (crysis engine?), which I genuinely used to test stability of my cpu. 8 threads fully loaded and probably with some form of AVX.
Reviews of upcoming Mount&Blade also note how it loads 16+ threads (mostly for NPC on battlefield).
Arma3 was notorious for being bound by single thread performance and low latency memory.
on a old midrange i5 6500 b5 does a solid 30+ fps on ultra and cpu load doesn't top out so I find the claim that it needs a top of the line cpu very dubious. I'll try armored warfare since it's free.
also, the fps reduction seems more in line with the low end intels having less pci lanes, and not the game being cpu capped.
Very few people genuinely notice the difference. I ran a 3600 while waiting for a 3950X, and if I had it to do over, would probably have just gone 3900X to start with... For the most part, I don't notice the difference, only after I'm running a couple databases and a few services that are active to I even come close to seeing a difference in general use.
I know GPU and Monitor options are similar, and CPU/GPU combination in terms of balance are important. Unless you're going RTX 2080 or higher, then it's much less of a difference in general use anyway.