In regards to the UTK waitlist, someone on Draft posted an email last year in which a staff member at UTK told them the waitlist was 83 people long. But that was last year.
In any case, my UTK waitlist notification was pretty boilerplate, so I wouldn't be surprised if the waitlist is super long. I think in many cases when a program is super serious about waitlisted candidates they make an effort to connect with those folks on a more personal level. My partner is a DGS for another discipline, and he actually sets up virtual meetings with waitlisted candidates his program is serious about! And those meetings matter, because he gathers a lot more information about candidates from talking to them in real time.
That's not to say it's not validating to be waitlisted. It is. It's worth something, even if we don't get in. Somebody thought our writing was good enough for their program. I will take it as a sign of encouragement!
Also, I don't think UTK is super high up in the rankings, so they need to have a long waitlist. Or at least that's my understanding. Maybe I don't have access to all the rankings, but I think UTK is pretty average as far as rankings go? That's what I would say in their defense.