I'd assume whisper will be better than YT auto ones for sure, especially if you choose the right model
On one source I tried the other day, the first 90 seconds or so is just generic opening music, no speech, but it "transcribes" it as "This is the end of the video. Thank you for watching. Please subscribe to the channel if you like. See you in the next video. Thank you for watching. Please subscribe to the channel if you like. Thank you for watching. ..." If you help it along by cutting up the source into only spoken segments you can get it to do better but just throwing it at a directory of material is probably going to leave you with some disappointment.
Then sometimes it does something surprising, on a j-pop song after hallucinating a bit during the intro it spit out a translation in the form you might find on a lyrics site, that is each line was "japanese-characters romaji-version english-translation". I haven't been able to get it to do it again (even for the same source).