Well the youtube comments seem to like it but IMO that is a pretty awful ad since it didn't use the opportunity to highlight their product. It practically shows more reasons not to use firefox than to use it.
We hear that firefox is private in some unspecified way, and... that's about it. The rest of the ad is talking about how everyone left it in the first place, that it comes bundled with default-enabled AI stuff you don't want, and that the internet you might want to use it with no longer exists. Talk about a self own.
Why did they not talk about customizability? Compact mode? Adblock support? Colors and theming? Syncing? Anything at all???