Actually, most games don't "require" 16GB or more. In fact, there are few games that require 16GB or will even use it. 16GB is plenty for ANY game out there, and 8GB is plenty for the majority of games out there. 8GB is "sufficient" for pretty much any game out there, although there ARE a few that in some specific scenarios may do a bit better with 16GB. I don't know of ANY games that require 16GB or more, at all.
Now, if you're running a LOT of other stuff alongside the game engine, then it MIGHT be beneficial. Tons of browser tabs, memory intensive applications, VMs, etc., all might increase the demand for memory but without those things then the number of scenarios where more than 16GB would be beneficial to the average gamer are very, very few.
This sounds more to me like either a combination of factors or possibly a virus or borked Windows installation.
How long have you had this hardware/system and have you done a CLEAN install of Windows at any point after it was assembled or are you running on a Windows installation that pre-dated this build?
Is system restore enabled?
Is automatic TRIM or defragmenting enabled?
It might be helpful to open task manager, then on the bottom left corner click on "More details". Then click on the Processes tab. Then click on the top of the CPU column to sort it by most resource usage and take a screenshot. Post the screenshot here. Do the same thing with the memory column as well.
And contrary to the offered advice, in MY opinion, automatic driver applications like driver booster or any other automatic driver software should be avoided. They cause more problems than they have ever solved and they are not the proper way to ensure you have the most recent and relevant drivers installed.