This is really just an example of Bike Shedding.

Reviewing research papers is really, really hard work to do well. It takes a massive time commitment to truly digest and understand novel work to the level where you can provide a quality critique and review.

It's much easier to throw out facile critiques like the ones these reviewers provided. It shows that you know your stuff and did your job as a reviewer, without requiring you to actually understand the authors' innovations or lack-there-of.