hypercritical
excessively critical
Root
- hyper-: over, beyond, or excessive
Hyper means too much or beyond. Hypercritical judgment turns criticism past the useful point.
The review was hypercritical about harmless details and missed the strength of the argument.
Criticism can help. Hypercriticism usually cannot. The prefix pushes the judgment too far, until the critic seems more interested in finding flaws than in finding truth.