I'd say it's more than branding with mullvad. Their actual onboarding is made completely frictionless and unidentifiable. They could run all of the same branding and still have a email login and no one would disqualify them for it, yet they go out of their way to not collect emails and also have crypto payments as an option to bypass the payment rails.

The way I see it, fundamentally the differentiator between vpns is mainly trust that they won't compromise your data, and I haven't seen any that I believe more than mullvad though I am open to suggestions. It also helps that it just works flawlessly as well. I can set it to cycle between various US locations and it's genuinely a better experience than not having a VPN on even while switching servers all the time.