New games should work in Windows 11. Windows 10 is basically if you still play old games that were developed before Windows 11 launched. But remember those big famous games are still developed in Windows 10 including new games such as Battlefield 2042 and Call of Duty: Modern Warfare 2.

New games no issue. Old games then the answer might be yes, if the game developer didn't patch it for Windows 11.

Upgrade usually will cause a lot of problem. I always recommend to do clean installation. Make sure after clean installation, download all the latest drivers from the hardware manufacturer website. If you using Windows driver, definitely you have a lot of issue.

Recently, I help my friend to troubleshoot the issue where his games got no sound but outside game we tested with Youtube and VLC, it play the sound nicely. So I go to the motherboard website to download the audio driver. Install it then reboot before relaunching the game. It solve the issue.

Another issue was with my dad desktop, after he upgrade to Windows 11 from Windows 10. All the graphics especially text look blur. Again I download the latest driver from Nvidia and it solve the issue.

Recently, I was busy with my work. I ask my Helpdesk team to upgrade my hard drive to SSD. They skip the steps of download the driver from laptop manufacturer (DELL) website. My Skype and Webex can't work properly with audio and webcam when they return my laptop back to me. So I have to download and install the driver back in order for them to work correctly.