I agree - there's been a decline over the past couple of series. And I don't think the " new " presenters have helped at all.
Jon Bentely seems incongruous in the show now, given the slant is for "zany energy" - and it makes him look like a dad at a disco - a little cringy to watch.
Which is a shame, because he's very knowledgeable and thorough.
Otis doesn't appear to bring anything to the table, really - except perhaps for a more balanced ethic mix. As has been said, I get the sense that he would be equally "excited" about a toy or a Harry Potter movie review - in a CBBC way. Not really a gadget man, just a presenter.
Give he's not that good it smacks of tokenism - although I'm sure that wasn't the intent.