Given how cleverly the authors tried to evade peer review, the evidence might have been quite flimsy to begin with.

Peer review is the primary mechanism by which modern science verifies evidence, especially in fields like climate change where it's often very difficult to replicate another scientist's data.

Evasion of peer review is like including an obfuscated blob in a critical part of some security software. It is highly suspicious by definition, and the community has every right to assume that it is malicious unless the author can demonstrate otherwise.