I have 5.9 kernels running fine on two laptops with intel graphics. Have you investigated what exactly stopped your systems from booting?

It hangs when trying to load the i915 module. CPU goes up to 100% and display goes black. Obviously it works with some, probably most intel GPUs but seems they aren’t bothering to test it with the older ones anymore. There’s a bunch of bug reports about it, so it’s not just me. usually they get closed with some list of voodoo kernel parameters that supposedly fix the problem but none of them fix it for me.

Damn, that sounds frustrating :/

Which distro? That's very weird because most of my drivers problems are usually solved by updating the Kernel.

I’ve tried several distros and every updated kernel up to 5.9. No distro works if it has a kernel newer than 5.6.

Please report this bug.

I will if I get time, which is unlikely. Intel is not a volunteer-run organization nor even a small company so I'm sure they could afford a test-bed containing one of each of their GPUs to test their drivers before release if they cared about this.

Just report it, it is their responsibility to reproduce and fix it, since they are paid for it.

Yes, Linux and regressions, it is quite common and frequent annoyance. Many times I regret for not using some LTS distro, but stalled/outdated software stops me from making the switch.

If only you could have an LTS base system with up to date applications. Sadly, the distro+repo+package model does not handle this obvious use case well.