I'm fortunate enough to own both systems (Xbox is mine, PS5 is my partner's) and with that said I'm delighted by this recent trend.
I'd prefer a firmer commitment to it, because I wouldn't feel entirely comfortable with only buying the one console for now, but it's a good step forward. That said it's probably an admittance that Microsoft and to a lesser extent Sony agree that at some point the idea of having a dedicated box under your TV for games is going the way of the Dodo.
If I was in a position where I could only afford the one system, I'd be much happier if it was in-house games that remained exclusive. I know I'm not playing the new Sony Spider-Man game if I own a Xbox, and I know I'm not getting HALO if I play on a PS5. Where it gets tricky Is when 3rd party titles get exclusivised (I'm making this a word), or even time..... exclusivised. You can't really predict that, and it just seems incredibly anti-consumer.