I know it's not profitable for this site to serve V.P.N. customers, so they're trying to fight it. They will quickly expose you and block you if you have a free V.P.N. service, as these servers have very weak protection.
There recently has been one major software company offering a free vpn, and the explanations don't make any sense.
What may be happening is that the streaming services are preventing playback with vpn so as not to violate market restrictions. 5 years ago there were definitely albums I could stream on Spotify because of these restrictions e.g. Law And Order by Lindsey Buckingham, the album is now available for my region.