My brother and several friends game exclusively on Xbox. So I have a PC and an Xbox One X or else I wouldnt be able to play with them, simple as that. But if every game was Play Anywhere then I could sell my Xbox, although Id still be buying everything from the Microsoft store so its still a win for them anyway!
For me personally, If is stop buying Xbox in favour of PC exclusively I still wouldnt be buying a PS4. Not enough time to play everything, not enough compelling exclusives (remove the Sony 1st party games and a lot of the other compelling console exclusive is still on PC anyway), and fact is most of my gaming time is devoted to multiplayer games like PUBG, Ark, Overwatch, Forza, Fortnight, etc.
The kind of scenario we have people talk about here is mostly seen on hardcore gaming forums. Most people dont own several systems and honestly dont care about all of this stuff. From what I have seen, the more disposable income people are usually the older people and because of work and family they dont have time to play (like myself). So what they usually end up doing is buying only 1 system; either a console because they like something simple, or a PC because they only want the best. And I see it everywhere, I personally dont know anyone anymore (now that I and all of my friends are in their 30s) that owns more than 1 system (now majority is on PC), and its not because of a lack of disposable income, its because no one has time for that.
Exclusives doesnt matter for those people. The only time i see it brought up is when list wars happen online, because once you get off your computer and go to the real world where normal customers buy their system at Walmart or bestbuy, nobody really cares. Theyll buy the cheapest and most powerful one theyve heard of, finish the generation, and do the same thing next gen basically.