Blunt force approach: open Spotify in a browser, open the playlist in question, scrape the HTML.

Tune My Music is legit. It is what Deezer uses if you transfer. I think if you do it through Deezer it’s even free: https://www.deezer.com/explore/en-us/features/transfer-playlist/

haven't had problems with Zotify for downloads when using the download realtime option. spotify also has the option to export your playlists. it's on the web in the account settings I believe? if you have jellyfin as well there's a plugin that pulls directly from the site as well

https://github.com/Viperinius/jellyfin-plugin-spotify-import

I've used Exportify (https://github.com/watsonbox/exportify) to get CSVs of my playlists. I do it for kind of disaster recovery scenario, so I've never actually had to re-import my playlists. Judging from the readme it seems it's possible but tedious. And as for importing to a different service, no idea.

It does require you to log in with your Spotify account though. But I think it's trustworthy enough and also you can self host it.

I've recently had succes with Soundbound, made by the creator of Spotiflyer.

I did a data takeout and got a legitimate definition of all my playlists, why don't you start with that? Perhaps its not available in all geos?

https://support.spotify.com/us/article/data-rights-and-privacy-settings/

I’ve used SongShift before to transfer playlists between music services. Looks like it can also export them to a file.

I found this one a while back for the purpose of having a local copy of what I've put in my playlists. https://github.com/caseychu/spotify-backup