Hiring Manager here. You can get technical questions added to the required behavioral but most managers don’t bother. It gets pretty hairy when you try to get them approved by HR who rarely understands them (fair enough) and you have to justify how they are relevant to the role and what the e expected answers would be.
That being said, I worked on a team that had a couple approved and sat in a panel for another team who had some approved. Candidates that have in-depth, realistic responses to the behavioral questions hit the technical ones like a buzz saw. And, to be fair, at least in the team I was helping I think it would have been pretty rare for a candidate to roll up with eloquent and correct responses to their questions.
When I asked that hiring manager what gives on those insane questions he said he’s not really looking for an actual answer but more a way to look into someone’s thought process. Yeah, so why not present a scenario and ask for the process you’d go through to approach it? Meh, would be too easy and make the candidate think they did a good job. You can’t make this stuff up.