It is not entirely a free-for all (as in, anyone can submit papers), there is an endorsement system [1]. Of course, it's only networking and who-knows-who - but

It is not entirely a free-for all (as in, anyone can submit papers), there is an endorsement system [1]. Of course, it's only networking and who-knows-who - but there is controversy, as in established contributors think that the endorsement system is too high a barrier. [1] https://arxiv.org/help/endorsement https://arxiv.org/help/endorsement