'Team Based Game'
Sure, by marketing, but when playing with the public, it's mostly a play alone game. People SAY they want 'team play' but they MEAN, 'Do what I want you to do when I want you and tell you to do it!"
If you removed premades, then you would literally have none team play at all. You can look to Overwatch to see what kind of disaster that turned out to be, with forced character roles and other stupid mechanics to try to force people to 'work as a team' rather than simply giving them incentives enough to.
Apex Legends does not incentivize public team play. In fact, it favors ignoring your public team mates. Only premade teams act like teams, mostly also and not always. Sure, I get there's a difference between a server with premades and servers without, the premades have a big advantage.
Still, you'd have a massive population drop if you forced only premades, so the best option is to make sure you have different server games. One with only premade teams, and the other with only public teams. I'm not sure that's feasible, but then at least you'd have a team marketed game with premade teams facing premade teams, and then a bunch of people running around no longer buying into a marketing illusion and understanding what it is really all about when you are playing in public.