That’s the very reason they are having to give up proprietary Royalties & go for an OEM.
Xbox storefront is simply not selling enough games for developers to bother & icing on the cake is the marketing & development deal that Sony offers in exchange of console exclusivity.
M$ can very well offer the same deal but the lost sales on PS is too big a hit for them to take that.
Once Xbox is gone Playstation won’t be able to convince developers to not release their games on this new OEM….as it’s simply a PC & PC sales(over the years after launch) are too big to let go just like PS.
Xbox just has to die if M$ wants to stay relevant in gaming.