I haven’t run Jellyfin outside of docker in ages, but looks like you have at least one set of conflicting tags in your exec section of that service file you posted (web something or other I can’t see on mobile once starting this reply - you have a flat setting it and a flag disabling it).
Edit - also do you actually have something set for that list of variables in your exec?
I’m sure the investors weren’t selling him on the idea that if they got a bigger return he would as well, surely.