On closer inspection, it seems Mediafire has a max 2GB file size limit for free accounts, so that might not be viable.
Pixeldrain (https://pixeldrain.com/) is another service I have seen other AVN devs use as an alternative to Google and Mega, and they allow up to 20GB files, no account required.
I have downloaded successfully from them in the past, so that might be an option you could look into at least for public releases.