Yeah if Varsho can return to being a 4-5 WAR player in 2024 and 2025, I don't think many will be regretting the trade in the long run. He's definitely the X factor. Like you said, young CFs with control can be very expensive and difficult to acquire.
We don't know the discussions the Jays had with the D'Backs and other teams regarding their catchers. So to say the Jays should have kept Moreno over Kirk is a moot point. Glad to see Moreno having success in the second half as well and hope the trade does work out for both teams - Arizona is one of the teams I like to follow in the NL.
Also, I think Kirk can bounce back somewhat and be decent offensively in 2024 if he gets himself into better shape and rediscovers some of his power stroke. I'll take Gregg Zaun offensive output from Kirk everyday of the week, which I think he's capable of doing given his OBP skills. Add in his plus defending behind the plate, Kirk can be a solid overall player for the Jays moving forward.