I think Sebbbi said t best that if you cannot guarantee you can deliver it, you will not put it in the scope of the game. So often many companies have research teams that do this so that their next titles can include these technologies.It is those "technicalities" that make these features a waste. In the case of Direct X 12 you know it is here to stay and eventually will be used. For Pro? Things are a little more shaky. The feature support matters more now. In a few years it will matter more for PS5
It's only been 1-2 years with Pro, asking companies to deliver on this, is asking a lot. A game company would have had to completed their research have no issues with it and begin starting a new game.
Existing games are unlikely to be able to implement this right in. A few can sure, but not all.
If the feature is worth keeping you will see it in future iterations.
Look at the XBO command processor customizations, they continued to iterate on that for Scorpio, and I imagine they will continue further development on this for the next console.