I understand why some comments should be removed. However, it does appear that there is a cleanup going on at the moment with any comment that is not directly adding to the answer or providing clarification being removed.
Of course, I may be wrong but, if there is such a cleanup going on, what is it's motivation?
As an example, I quoted one of my favourite aviation quips in an answer of mine - "in the ongoing battle between the Earth and aluminium objects arriving on it in other than controlled conditions, the Earth has yet to lose" - which generated some comments, light-hearted in content and expanding further upon it.
Whilst I accept that the comments add nothing to the content of the Q&A, and I personally couldn't care whether the comments on my answers are deleted or not (unless they are substantive), I firmly believe that additional comments such as these bring some humanity and reflect the nature of this community to the wider netizens.