As someone else noted, I'm considering overwriting the EEPROM in the monitor but I'd like to be 100% certain that's correct before I try it (one of the reasons I posted to HN was to see if folks thought I was going down the wrong path). I'm actually going to try a completely new cable first in case it's a bandwidth issue.
I definitely had the same expectation, & was most way through reading, expecting my expectation wasnt going to be mentioned, but I was far from upset. I was quite happy to hear there's kernel workarounds for exactly this kind of thing.
The main shortcoming I feel right now is that this only works if you only have one specific monitor you want to hack, or you are ok rebooting. If the kernel had some way to dynamically override the edid that would be excellent. Maybe a eBPF filter?