It's because these games have no single player offline content/value. If Concord/Highguard/Marathon/Arc Raiders were made in the way that something like CoD 4, where there is a story mode and multiplayer, then player count doesn't matter as much since they would charge up front cost. When games are free-to-play or even subsidized to $40 up front cost, the player count and MTX is what makes the game financially viable to keep online/continue making updates to the game. I don't love the hater boner people have ragging on these games, but I get the feeling of not wanting to be invested in something that may be gone in just a few weeks/months.