Obscure tech is also an opportunity to be one of those rare specialists in a field. A Linux expert still gets rewarded more than a Windows one in a desktop management role, though it's certainly harder to find a job in the first place.

But this is also a personality thing. I prefer being a specialist on something unique over one of many on a big team.

I agree with you that when the obscure tech is simply the wrong one for the scenario, it's bad. If you don't believe in it yourself it's really hard to commit to it. In that case it's probably better to find another position or even another company..