Note by @FrenzyBiscuit

@InsertUser @peertube Well how do you purpose the video is cached?

I believe (not positive) that its currently stored in RAM.

If you have a 20GB 4K video, that is 20GB RAM usage. Nobody wants that.

If you store it on the disk it uses up 20GB write cycles per video and will burn through the SSD/NVME. People will be angry.