Carmack actually commented on that in
an unscripted video that he had at Meta's Connect event. Surprisingly, they allowed him to be (seemingly) rather honest in his feelings, which isn't something that you'd expect from a renowned member of a huge corporation. If I recall -- I read the article a few days ago -- he doesn't dislike the functionality of the new headset, but it isn't where he thinks VR needs to be going.
The Quest Pro might not be too bad if we get a trickle down approach. For example, if the (eventual) Quest 3 has the self-tracking controllers, that would be a nice upgrade. My biggest thing with it is that I'm hesitant about the strong push for AR in addition to VR. I don't think there's anything wrong with AR, but if the features to support it are jacking up the price tag that affects the already existing and prominent VR portion of the HMD, then it's a problem. The most problematic aspect is probably that AR doesn't really have a "killer app" where people can just point to things like Beat Saber or other fitness programs for VR.