Again it’s not a traditional video file. Iirc its a series of really high quality unconpressed images being played back at once with audio. The max resolution is is 4k but even the 1080p films can be 100gb. The real knee slapper is when the video’s resolution is 4k but the projector is old so it can only output max 1080p.
The movie at a cinema isn’t a regular mp4 file, it’s a massive 100-300gb proprietary file that needs a valid license key to even be played back during a specific time period. Good luck decrypting the file or getting the company that issues the keys to the cinemas to give you a key because you’re not getting it to play early. Iirc somehow the Korean rip of the Sonic the Hedgehog movie was leaked early and something similar happened with the My Little Pony movie, but those fan bases are incredibly autistic and will find a way.
BIOS and emulator files
I know it’s not self hosted but why not Signal? Matrix is demanding on a SBC and your family would probably get the ‘unable to decrypt message, please re-verify keys’ error that happens in encrypted matrix group chats and Element does not have the best UI especially if you want your grandma to use it.
What? Did you record the rented DVDs on blank tapes or am I misunderstanding?