Now it should be fine

I just tested and noticed this is generating one file per playlist rather than a single file for all the playlists as I believe is intended. So currently I would consider this a regression rather an advancement. There's also the existing issue that you don't get any log file if the script exits early due to an error.

So I would recommend that you should rather use the standard python logging library to fix these two issues

I am currently unable to debug this, as I can not find a playlist with unsyncable songs.
Would you mind sharing a playlist that causes this issue?

Here's an album that fails, you could create a few playlists with diffrent tracks from this album to reproduce the issue I mentioned
https://open.spotify.com/album/0Pkamaa0inrBIDaZn6odNB?si=_rjtX5TEQnOmBIwQBfn2cw