I don't think it's hypocritical in the slightest. It's like a job. You have Company A and Company B. Company A's CEO just stepped down (Babs), and now two leading candidates to take over (Steph and Cass) both are executives (superheroes) in the company, have years of experience with the team (working with the Bat-fam) and the corporation, and have a long history in the field (20+ years in comics). They both make since as successors.
Then you have Company B, whose CEO is well-established (Bruce). You're not going to put random, dude from the street (Jace) who has no executive experience in the company (no superhero experience), have no experience working with the established team (only Luke from the Bat-family has had any interaction with Jace), and no history in the field (hasn't appeared in 20+ years.)
Nobody's going to say, "It totally makes sense for Company B to hire random dude with no experience just because Company A may be promoting those two, highly-qualified and experienced candidates. Random dude says he wants the job, so I guess it's totally comparable to having the history and experience."
And once more, I say this as someone who is totally fine with Jace Fox- and has been reading his appearances. I do think the argument that someone has to accept it makes sense for every potential for mantel-sharing to be okay, or absolutely none of it, it nonsensical and frankly ridiculous.
It's like the scene in The Dark Knight where Bruce stops the three randos that have all dressed up like him. None of them had the experience or skills that he did, and they would get hurt if they continued trying to take up his idea without any training or experience. One of them even gets killed by the Joker later, proving the point.