I did exactly the same argument earlier, that in big organisations, disclosure and communication is heavily controlled. And AMD have not even set up a dedicated Linux forum!
Now saying there is absolutely no acknowledgement is not entirely true: a few tickets have been filled and @amrits has posted multiple times in this thread their filing numbers.
And I reckon that owning a 5080 I may be insulated from performance loss, because I can play at 60 fps instead of 80 with the same enjoyment.
That said your reporting was stellar. Hopefully this will be resolved this year.