So I struggled to delete a free Apple TV+ account for a day now (tried different browsers etc) and decided to search if anyone else has had the same problem. Turns out this issue is at least a year old, is known by apple and the Apple support suggests to find someone else with an Apple device to help you out.
Streaming was a solid option for a while, but these days I've found it's so much easier to just torrent. If it takes up too much space, just delete the file when you're done.