I understand the intention of an image thread to be that the subject should be a collection of images. But not in the sense of just posting pictures and keeping quiet, rather that the depicted subjects may also be discussed. So that essentially houses or construction sites should be the topic, as opposed to floor plans or calculations. But if I just want to like pictures, I can do that on Fb&Co.
I see it exactly the same way. A forum lives precisely from such discussions.
However, some have to be a little careful not to misuse the anonymity of the internet.
Criticism is good and welcome and fortunately mostly very constructive here. On the other hand, one has to be a bit careful not to be too harsh on the builders. For many, this is one of the most important projects of their life, so sharp criticism can sometimes "hurt."
In the end, of course, everyone who puts something on display and/or expects feedback has to deal with that.