Yeah I don’t fully understand either. I think the point that folks were making was about port forwarding allowing for much better speeds? I don’t have Mullvad, but I know with my vpn my speeds are crippled when torrenting on it, so maybe others have similar issues with Mullvad without port forwarding.
It could be their goal is not to be folks primary casual browsing instance, so just being someone that is stopping in to hang out isn’t quite what they are looking for.