can the people who use this say why this is appealing?
You always have to pay on console if you want to play multiple player, it's not just Xbox.
As for single player games, just do the math.
If the amount of game price that you want to play next month > sub fee then use subscription services.
If you play less than don't use sub.
Whether it's appealing or not is entirely a math issue. You have to do the math yourself based on your own purchase habit.
Personally I only sub when I have more than one game that I want to play next month and those game price > sub fee. Then I unsub once I am done with those titles.
The whole point of sub is to save money from buying games and try games you normally wouldn't buy. Use it as a demo library basically.
As to why the highest tier price has to increase, I think doom dark ages is a good example. It's a 10hr game cost $70, so a lot of people just play on game pass day one instead of buying it. Then the game has low launch sale on Steam because of that. Any launch day sale loss for those $70 price game is money that MS has to pay for getting game pass sub.