Comment 10 for bug 1976147

Yes, simplefb was turned into a module in 5.15 so that is expected. But I didn't expect this to make a difference given that it works just fine for me. Looks like your monitors can't render whatever the dummy console driver is outputting or something.

I flipped it back in a test kernel. Can you give this a try:
https://kernel.ubuntu.com/~juergh/lp1976147/