I had one 5e campaign set in L5R where all PCs were technically human, but I let the PCs pick whatever race statblock they liked and reskinned their racial abilities as supernatural techniques passed down within their individual clan or family line.
I did not have the L5R splatbook at the time so I was just manually reskinning the PHB and the monster manual to the L5R setting. Worked great.
Lots of little things, but the straw that broke the camel's back was the constant pop-ups asking me to try out Copilot in Win10, harassing me daily on both on my personal PC and my work laptop.
Windows has been on thin ice since the trash fire that was Win8, and I'd only stuck with it for Nvidia driver support for gaming. I've been watching Proton development for years now, and putting it through its paces on my older PCs every few months, so I knew I was ready to make the switch for about a year before I finally pulled the trigger. I justified putting it off with the thought that "I can build my next PC around an AMD graphics card amd make the switch then."
Then Win11 and all its garbage was announced, AI took off, and Microsoft started pushing their slop on my machine harder than ever. It was too much. I switched to Mint DE on my current machine and haven't looked back.