Some games just run awful because they were poorly coded.
Some games don't use more than 1 CPU core.
Examples of poorly optimized games I've encountered include 7 days to die, PUBG and STALKER Call of pripyat (with dynamic lighting). You need to spend a bunch of time tweaking the graphics settings if possible to get a good fps.
Meanwhile my PC can easily run GTA V, Fallout 4 and other titles on ultra high graphics and sustain up 90-100fps no problem. Looks bloody terrif on a 144hz gaming monitor when I hit those high frame rates.
I just upgraded my computer.
I am finding out really fast that some games were being held back by my limited hardware but many of the games that ran kind of shit were because of poor optimization and shitty coding issues. Meaning that a few of the games could be run on a super computer and still have a trash frame rate among other issues.
if you're serious about getting good performance, I recommend getting revios 1909 and disabling as much windows crap as possible with the help of n1kobg. A random autist that wanted battlefield to run better is indeed smarter than the entirety of microsoft and linux morons combined.