If we are dealing with constructive criticism, does it matter if folks point out issues instead of pointing out positive elements? Why would folks need to spice up their posts with off-topic positive comments just for the sake of posting positive elements?
If the posts bring absolutely nothing constructive to the discussion, report them and get them removed. Or respond to them and showcase how shallow they are.
But it's utter bullshit to be running around and going "somebody posted something somewhere and now the whole thread/forum sucks". There's absolutely nothing productive about such comments.
With that in mind, there's probably nothing on-topic about this discussion either.