Does Sony have no say on how MS delivers the game? No matter how you look at it, it’s an L that this is included on GamePass and we have to pay $70 for it on PS5.
The MLB decided that. They seem to want it everywhere which makes sense for a sports game. I'm guessing Microsoft tips the MLB to get it on Game Pass. With the Gold conversion trick it's possible to get 3 years of Game Pass for just $11 over the cost of just the last 2 year's MLB games alone on PS5.
3 years of Gold can be found for $150 on sale or at places like Sam's Club. $1 more converts all that time to Game Pass Unlimited for the 3 years.
MLB The Show 21 and 22 cost $140 combined.
Also this came has cross platform saves, progression, and play.