I'd take post-processing over nothing, wouldn't you?
Not that I expect any further development however minor to happen on the consoles now. This is as good as it gets for the forseeable future I think that's clear. Unfortunately.
Indeed ... a very sorry state ....
Given the delay to Odyssey ... and that they clearly have 4K assets for the game already ... I wonder if it would be possible to build an alternative PS4 version of the game but compiled with the 4K assets and rendering at 4K but then release that ONLY for the PS5? Would still run in backwards-compat mode now with 4K ... without impacting the “true” PS4 version ...
Anything like that would win them some serious brownie points whilst they work towards delivering the PS Odyssey DLC which, realistically, will be out “end-of-2021” now.