I think it's hard to tease out the size of effect. Extensions are only used by a minority of users, but that's mostly the set of vocal power users that are likely to be the go-to tech person within their social circles.
I'm sure I'm far from the only HNer that has recommended or installed Firefox for many friends and family. I mean, I used to recommend and install Firefox before their terrible management turned the org into a dumpster fire. They've lost both myself and everyone I would have turned onto Firefox.
That might have been 20 years ago when Firefox grew from it's grassroot-movement. But Chrome started without extensions and grew more through marketing and Googles fame. Power users have their influence even today, but I'd say it's not as strong as it was in the old days. Most users have emancipated themselves from us, and can choose now on their own, because this kind of information is not arcane anymore.
I'm sure I'm far from the only HNer that has recommended or installed Firefox for many friends and family. I mean, I used to recommend and install Firefox before their terrible management turned the org into a dumpster fire. They've lost both myself and everyone I would have turned onto Firefox.