Well, at risk of going on a bit of a tangent here, realistically my experience in every field is that a distinct minority of jobs ever get filled through formal job advertisements. The vast majority of hiring happens through referrals and networking.
Bringing it back to tech specifically, in my (anecdotal) experience people are rarely bothered by lack of knowledge of a specific framework assuming that the candidate has experience in something similar, or more generally if it is safe to believe that the candidate can get up to speed and contribute in a reasonable amount of time.
At this point we are of course just comparing anecdotes. I will also note, though, that there are a lot of very different subsectors within tech, and hiring practices vary widely between them. In accordance with the venue I am here mostly referring to startups (including late-stage startups).
Bringing it back to tech specifically, in my (anecdotal) experience people are rarely bothered by lack of knowledge of a specific framework assuming that the candidate has experience in something similar, or more generally if it is safe to believe that the candidate can get up to speed and contribute in a reasonable amount of time.
At this point we are of course just comparing anecdotes. I will also note, though, that there are a lot of very different subsectors within tech, and hiring practices vary widely between them. In accordance with the venue I am here mostly referring to startups (including late-stage startups).