I will say that I have serious doubts about the long-term longevity of the framework the plug-in uses to get lyrics. It seems that lyrics in plain text at easily predictable URLs are becoming more rare, and throttling of requests is becoming more common, and I don't see any indication that either of those two trends reversing. If someone is really going to do something that goes beyond maintenance and make it sustainable, it may be worthwhile to study what it is about that foobar plug-in that makes it works so well.
Yeah, after giving it a bit more of a look, I just don't see this as being viable much longer, unfortunately. The code is just too simple, and even with the few changes I could make to improve the capabilities in lyric parsing, the config files would be even more complex and still require frequent upkeep for as long as they even continue to work.
But the bigger problem is that the YAML files just aren't sufficient for adding lyric sites to LyricsReloaded. They simply aren't powerful enough to specify enough information to the plugin's generic parser. Trying to move forward with YAML would be an unmaintainable mess. The simple truth is that each lyric site needs its own parser written in code.
You're also right that relying 100% on page scraping won't be good long term, but adding API access capability to this plugin for sites that allow it would be another major addition. That with the YAML change, which I think are necessary, is essentially writing an entirely new lyric plugin from scratch.
Man I am "clamoring" for it.. frankz made this sucker work well past its shelf life, but it's obvious how hard it must be to stay on top of the changes these sites make. Redearth I encourage you to give it a shot, there are PLENTY of users who would take advantage of this but like me just don't have the technical chops to write the code. As an inspiration I can refer to the complete resurrection of lyrics searching in the Foobar player when ONE GUY with the required time took the challenge to write the foo_multisource plugin that currently has ELEVEN working sources--Genius, Deezer, Metal Archives, etc etc. It would be so cool to see MusicBee in the same place. Please give it a go.
foo_multisource isn't actually a plugin, it's a collection of parsers he wrote for the Lyric Show Panel 3 plugin, which he did not write. The plugin is much more complex and powerful than LyricsReloaded, but it still requires updates to the parsers whenever non-API lyric sites change their page structures. The author of foo_multisource even said his parsers aren't stable, and he has put in a ton of work into creating and maintaining them. They happen to work really well right now because he literally just released an update.
Also, it looks like he might rewrite the parsers for the foo_openlyrics plugin since Lyric Show Panel 3 is dead. foo_openlyrics is also a great plugin, but it's also substantially more complex and powerful than LyricsReloaded, but still requires parser upkeep.
So, sorry man, I just don't see it happening for MusicBee. Foobar attracts a very passionate and dedicated dev community.