I’m really sorry for reiterating this, but what you wrote also implies that movies that weren’t on any list will also be deleted (don’t want that), along with the movies that were on a list and now aren’t (do want that). do you have first-hand experience with this?
I’m trying to utilize a couple of core 2 duo macbooks for the same purpose and it’s not going great. I have twice the cores and RAM but they’re stuck at 800 MHz, because of no batteries.
anyhow, very slow and issues with a lot of codecs I throw at them. try mpv without a DE/WM.