https://github.com/linsomniac/spotify_to_ytmusic
The biggest reason I ditched Spotify is that their shuffle play of playlists is laughably bad. I like listening to just a shuffle of my favorite music, but their player seems to "stick" on just a few of them. I ask it to shuffle a few thousand "liked" songs, during my shower every day, and I'll hear the same song 3 times in a week, for example.
There was a "bug" open in their support forum since 2017 that they replied "maybe we'll look at it eventually". It has hundreds of pages of replies. And they just laid off a significant portion of their workforce, so I figured it'd never get resolved. And for a company doing music playback, it just seems like they can't get one of the basics right.
Since going to YTMusic, I've been hearing songs from my playlists that I haven't heard in years.