I'm reservedly satisfied with Gigatribe I managed to get some rare content through it, the downside is that some premium users set up insane quotas, what also sets off my autism is that I can see that a lot of users have never subscribed to a model by the incompleteness of their collections.
https://www.transfernow.net seems like pretty good wetransfer alternative, the max upload size is 5GB and uploads can be protected with passwords which maybe can prevent them from being taken down automatically.