At the same same time if there is no entry barrier what stops people leaving for similar reasons to the one that brought it?
People will leave for all kinds of reasons regardless of entry fee or not. It's just that new ones will come easier and replace them faster.
See
Evolve has a perfect illustration of this.
So lets say we get huge increase in playerbase that means increase development costs in terms of running servers and the like but unlike before where there was a guaranteed(albeit of course refunds) return in revenue they instead rely on lootboxes/hero packs or similar(A bad model imo for this game) which are optional. It's a given in a F2P the majority of wouldn't be paying these things that help sustain development. Now the question is would those that do be enough to offset the increase in running cost and would it be a worthwhile avenue given it's potential to rightfully upset existing playerbase which could also put some off entirely from the game.
Then is also the factor to consider will similar things happen to it like with Evolve after a month of going F2P?
F2P advantages atm seem more of a short-term fix/boost than a long lasting solution.
The driving point is the constant stream of new players. I just checked out Dirty Bomb. Only because Brink went F2p and people said check out DB it's what Brink should have been. I loved it and bought the biggest Merc pack an hour later. There is absolutely no way I would have done it if I had to pay first. I thought the game sucks and isn't for me up to this point.
They don't need to remove the price tag for the whole package, just for entry and add a hero rotation. (or something similar, it's just one example) If the game is great and people love it (which I am sure they will) they'll gladly pay the 30 bucks. That don't have the money still can play and add to the player base etc etc.
And I am not saying it's the perfect solution. Evolve is a good example of where it didn't work. But I would argue that running in circles chasing something isn't really a fun thing to do in a game. It was just bad.
73 players was the lowest point today. It's at 205 18:30 CET, prime time. And Destiny 2 PC isn't even out....
Edit: There is a good chance nothing will save it and people are just not interested in more arena shooters... this is possible as well.