The thing I don't understand about Brave users is that they are essentially using Chromium with a bunch of extra bloat added. Wouldn't it make more sense to just use Chromium with the extensions that you want and need?
You absolutely could create a similar browsing experience (with excellent extensions like uBlock Origin), but you're still ultimately at the mercy of the browser vendor. For example, uBlock Origin is facing pressure from forthcoming Manifest V3 changes which threaten the existence of the extension (and many others like it). Brave, as a Browser, has committed itself to continuing support for these types of extensions.
One of the other large elements of Brave is Brave Ads & Rewards, and the ability for users to anonymously translate their attention into substantive support for content creators in a privacy-preserving fashion.
Sampson (Brave Team)