A wild gunnerkrig fan!

There have been plenty of cases of windows messing up boot configuration if dual boot over the years, though it’s pretty rare more recently. The last one was only a few months ago and affected systems using secure boot https://www.zdnet.com/article/windows-update-breaks-linux-dual-boot-but-there-is-a-fix-for-some-users/

You can do PGO with GCC, though it takes extra steps of course

Negative. I am a meat popsicle.