The Q7 Max+ does not have this function. As far as I know, the suction power is increased to the maximum and it stops moistening the mop at that moment.
Nevertheless, the carpet does not get noticeably wet and it even works surprisingly well NOT ONLY on short-pile carpets.

Unfortunately I can't answer this question as I only have tiles.

Yes, I think the carpet is wet, but the amount of wetness is low and you can control it via the app. The robot is doing a good job and is fine! But, there are many sensors problems! I need to return it urgently for repair!