I think your best bet in this case is google drive. Most people have a google account, and if they don’t, I believe it’s possible to set it up in a way that it will let them upload anyway. I don’t think you’re getting out of the account requirement, outside of you setting up an anonymous ftp server in a vps or something.

OPNsense for the win! It’s so powerful, I love it.

Well that’s disturbing.