Vanced isn't equivalent to paying for premium. It includes features like ReturnYoutubeDislikes and SponsorBlock which would normally be available via extensions (as would the premium's lack of ads via adblock), as well as further customisability.

It replaces some enhancements that are normally done via browser extentions and I personally find it extremely handy to be able to copy with a timestamp, set a video on infinite repeat, restrict video bandwidth on a finer scale (the native app removing this baffles me), set a default playback speed and reenabling tap to seek (another baffling change).

I happily support creators and alternative platforms (Nebula, Floatplane) via direct channels, and personally I don't find the service or youtube as a platform worthy of support.