Taxonomy condition is not available

I'm maintaining this module. This is a feature request, so moving it to that. Feel free to provide patches to deliver on what you're asking for, happily accept something that gets the basic functionality in.

Attaching a screenshot of D7, though it probably makes sense to split the functionality between the two matching types because I believe the "Vocabulary" condition matches "Match when viewing term pages" for Vocabulary matches

You could use the contributed term_condition module, if you need such a condition. I don't think this needs to be re-implemented by menu_position. I suggest to close this as works as designed.