For new "features" as AI improvement in 1.5 that older consoles can't handle, for sure. But for expansions (story), CDPR have no choice. They announced that they will be available on all platforms. So it's possible that some features won't be available on older consoles, but the main part (the story) will be available for everyone
And I don't think that adding few dialogue lines (or even a quest line) here and there would be a problem on "old gen" hardwares.
I truly believe that CDPR will homogenize the game across all platforms. But I think this will take some time and changes to the game's code base. A year is a short time for a game of the CP2077's scale. It involves a lot of mechanics.
Let's hope that this happens, that CDPR can meet all or most of the players' demands.