A handheld and highly integrated device where games released for are basically guaranteed to run still has some appeal over the wide sea of PC s. Especially since the share of handheld PCs like the Steam Deck is still comparably small.
I'd also argue that one can get more customers by supporting PC due to those who wouldn't buy a console anyway. It sounds reasonable though that the incentive for buying a console is gone if you already have a sufficient PC where you can play the game on.
But I wonder whether this is really the case. Do we have actual numbers from market studies or alike on this?
If it continues like this, it very well might ne some day. One can dream and hope...