I have a 1.5 yr old machine, i7 9700k, Gigabyte Z390 Aorus Elite MB... and a computer science degree.
Here's my experience.
I ran the readiness check... Failed.
To the BIOS! I then discovered my BIOS won't recognize when a keyboard is plugging in, I've tried everything, different ports, different keyboards.... well fine, I can use the mouse. Using the mouse, I have to disable some CSM settings, save, reboot, go into Secure Boot settings, reset factory default keys, in order or enable the secure boot mode, but! That's not enough, apparently I have to go back into settings, and enable Intel Trusted Platform something or other... however THAT can't be found, unless you go back to the Secure Boot settings and switch the Secure Boot Mode from Custom to Standard... and of course, the window that pops up when I make that switch asks if I want to reset some default so it can switch, Yes/No... that window, does not work with the mouse. So, I don't know what to do at this point other than try to find a way to get a keyboard to work in the BIOS in hopes that the window will respond to a keyboard.
Later, I found that the Intel Trusted Platform option has magically appeared buried in some Settings Miscellaneous area. After Enabling it, it now says my PC can Run Windows 11. Wow. Microsoft is shooting themselves in the foot. I'd hate to be on their phone tech support team.... Microsoft thinks the average user upgrading to Window 11 is REALLY doing to do any of this? It's going to be an EPIC FAIL... I guarantee you they will pull that requirement quick.