Usually due to copyright / contractual reasons. Have you tried using a vpn set to a different country?

Yeah I noticed this too. Not too much of a loss like you said, since the old version is still available.

What annoys me more, is two albums that I absolutely love, keep getting added and removed a bunch. Except they haven't been added back in a while, and I'm not sure they are going to return (╥﹏╥) . In case you are interested, the albums are: Evildead - Annihilation of Civilisation; Nuclear Assault - Survive.

Bear in mind however, the usual cause of this issue is typically either a licencing issue or the decision of the record label, so it isn't always black and white as to where the blame rests.