Try buying games on PC. I’d love to buy all my games on steam and keep them there. But no, every publisher now wants to run their own store with their own social network (usually one that doesn’t work well). There is truly a difference running one fairly good launcher/store vs 10 different slow start and resource hog stores.

Another example: would you rather listen music on Spotify, Apple Music or would you like to install Sony Music, Universal Music, Warner Music etc and always try to guess which artist is on which store.