Games as a service can be okay, in some situations. Ones we very rarely see due to (primarily) publisher greed.
If you're paying for the game itself, at any point, GaaS is stupid and extremely exploitative.
If they choose to go that route however, the game needs to be free to play with separate monetization. They need to mebe things that are completely optional and don't affect gameplay.
That's exactly what I did after Activision fucked over Infinity Ward. I used to play them all the time, but haven't bought anything Call of Duty since.
Doesn't mean much, but I'm doing what little I can.