I understand. I have read negative comments like that too, all too often: I’d encourage the recipients to read those not as ‘critique’ but, but rather as opinion, and opinion usually not well founded.
I think ‘critique’ requires both reasonable premise (I mean a premise within and related to the Image (artwork) and also reasonable explanation pertaining to the image (artwork).
For example (I don’t like using the word “negative” to describe ‘critique’ – but in this situation I think it is relevant):
“After the Concert” Subway Carriage - Vienna, Austria, 2014 (Fuji X100s, Available Light)
1. (Negative) Opinion:
“You were too close to the Subjects either get back further, or zoom wider”
2. (Negative) Critique:
"The triangle captured between the three girls works really well, it is disappointing that the exclusion of the boy is not enhanced by the image having a bit more negative space into which he can gaze."
Personally, I'd dismiss the first comment but note and also appreciate the second.
WW