You understand that, for everyone except for a complete network pro, that is worse for security and privacy, right?
Don’t get me wrong, it’s great that you can.
But the reason piracy websites struggle so much with long term stability isn’t because they’re hosting the wrong software.
Yup. If the sd card doesnt have enough space for everything, you could attach an m.2 hat to it as well. https://www.raspberrypi.com/news/using-m-2-hat-with-raspberry-pi-5/
Basically, jellyfin on the pi, with the wifi setup as an access point, and whatever amount of storage you need. The pi requires 5v/5a, so you’ll probably run into issues running off the car usb power, but a cheap 30amp hour battery should run it for 6-10 hours if my napkin math is right.