We have many whitelisted websites already.
Most of the time, when I come across some works with musixmatch.com links:

• musixmatch.com page contains no lyrics
• work has other links with lyrics

Some editors are still adding them, despite pages being empty.

2 examples:

https://musicbrainz.org/edit/77098890

https://musicbrainz.org/edit/96683924 editor says it's for whenever musixmatch.com adds the lyrics, but it's never done.

Let's just stop supporting musixmatch.com (currently 17,523 URL), even if maybe many are not empty.