I developed my own scraping system using browser automation frameworks. I also developed a secure storage mechanism to keep my data protected.
Yeah there is some security, but ultimately if they expose it to me via a username and password, I can use that same information to scrape it. Its helpful that I know my own credentials and have access to all 2FA mechanisms and am not brute forcing lots of logins so it looks normal.
Some providers protect it their websites with bot detection systems which are hard to bypass, but I've closed accounts with places that made it too difficult to do the analysis I need to do.
I use it to play music from Jellyfin to my Sonos speakers. It won't fix a Jellyfin library that has bad data, but it can pull in music from multiple different sources and push to different players.
It works well enough. Some issues where songs get interrupted, but I think that's issue with the Music Assistant/Sonos integration.