Ideally yeah to be on a secure OS after this October, which is when the Win10 ESU concludes.
There are ways to minimise the annoyances of win11 if they’re still apprehensive but you shouldn’t let them use anything that isn’t receiving regular security updates, even if it’s just for a gaming system.
I mean I would personally agree but I also feel for the skittish. They might also play games that don’t run at all on Linux, even even hw accelerated (gfx passthrough) VMs.