Reinstallation is not a problem at all - you have to just dump the installation folder to the install location, the program settings, tabs/playlists, library are taken care of - I don't think it gets much simpler.
About losing some settings on upgrading, the onus of backward compatibility lies on the latest release. I agree, some work is required but the last release seems to have caused this particular issue rather than resolved it.
That is only true as long as the foobar folder under appdata is intact (or program files if you don't use per-user profile). It is also impossible to share complete configurations without messing up your music database with the current version, whereas the new beta lets you import/export complete setups without touching you data. It's a whole lot easier to explain to someone that they should use the import dialog and open your config file than it is to explain to them that they need to locate the %appdata% folder (or the program files folder), overwrite the old files there with a bunch of files you copied from your setup, then having to re-add their music folders and scan them all over again loosing any additional data (play counts, ratings etc. if they were using components like that) in the process.
I also don't see how backward compatibility should be a requirement in any software product. This is one of the major problems that faces Windows, and one of the things I blame for making Vista the mess it currently is. Wasting time on fixing something that is broken by it's original design is usually not a good idea, when you can write something new that works better in half the time. Again, look at Windows, but this time Win9x. It was not written as a multi-user networked OS, and these functions wasn't really fixed or even really working until the move to the NT kernel in Win2000...and even there it is somewhat lacking due to the compatibility requirement with older applications. I'm not saying that Microsoft should have gone this route with Windows though, as compatibility is a major reason to it's success but I do think that it could have gained a lot (e.g. better performance, stability and security) from being able to get rid of the legacy code in there.
Going back to the topic of foobar2000 again, using simple config files is a much better idea than having both the configuration and data blended together in a mess, as it should (at least in theory) be a whole lot easier to make use of this even if something major changes is done in the feature. Also, it means that if one the items [data or config] gets corrupted, it doesn't mean that you loose both.
The next version of foobar2000 is not a perfect software product, but it's a step closer towards it rather than away from it so I don't see why one would feel the need to boycott