Part of the difficulty with valuing Ayers is that he's a unicorn. He was a 19th round pick who was largely unheralded until late last year, and even coming into this season the attitude was relatively restrained. The Cubs historically have done a very good job of developing catchers (Amaya. Caratini, Contreras, Castillo, Soto), so it's not like his breakout comes as a complete shock, but catchers who are way too old for A-ball tend to be more likely take the coaching career track than make it to the majors, much less hit the holy horsefeathers out of the ball and jump to AAA in a single season.
You can make the case for Ayers as a borderline Top 100 guy and teams will definitely have interest in him in deadline deals. The problem is, he's on a road that's rarely (if ever) traveled, so his ceiling could be anywhere from "backup catcher who doesn't get a second contract" to "if he's traded, you will get irrationally angry every time you see his name come up over the next decade."