I’d rather trust Google than Brave.
uBO is a wide-spectrum blocker, not merely an adblocker. It has powerful context-sensitive blocking that's surpassed only by uMatrix (also from gorhill), as well as cosmetic filters that I find invaluable for cleaning up the dumpster fire being passed off as "the web" these days.
Floating header bar that follows you down the page of an article you're trying to read, wasting your vertical screen space? Remove it permanently with uBO's cosmetic filters and never see it again. Tired of the sidebar with links to clickbait articles on the site? Cosmetic filter. Wikipedia nagging for donations despite a history of irresponsible spending and ample cash reserves? Cosmetic filter.
In other words, Brave is "wide-spectrum" too. We block tracking, fingerprinting, and other bad scripts -- not ads _per se_. This has the effect of blocking 3rd party ads and most 1st party (since 1st party ads still rely on tracking "pixels" AKA scripts for confirmation).
We don't block 1st party ads by default where they work without tracking cookies and scripts. A prime example are the search ads you find on Google and other search engine result pages. These are about as clean as you can get, and yet some of our users want to block them on principle, for aesthetic reasons, etc. So we are adding options to do so.
Cosmetic filters have a high performance cost that we have not been willing to take by default, but we're working on them.
Brave doesn't have all the Chrome telemetry (etc) as I understand it.
They were using Mixpanel before, but they got complain from users, so eventually they added a proxy in front of Mixpanel (but that doesn't change anything since Mixpanel generates an UID, so what's the point of hiding the IP ?).
https://github.com/brave/metric-proxy
It's used for tracking user performance when distributing BAT (otherwise you would have no referral program possible), that's how they distributed the initial 5 USD
For in-browser telemetry, please see https://brave.com/privacy-preserving-product-analytics-p3a/. Low-dimensionality data (a few bits of answer) given to randomly timed unlinkable survey questions; anything hi-D is in the future and will use PROCHLO.