Even if you do manage to get a tenure track job, you pretty much have to keep your head down for 7 years in order to secure your position.
And once you have tenure, you still get attacked vociferously. Look at what happened when Andrew Gelman rightly pointed out that Susan Fiske (and other social psychologists) have been abusing statistics for years. Rather than a hearty "congratulations", he was called a "methodological terrorist" and a great humdrum came about [1].
When framed against these circumstances, it should be evident that there is literally nothing to gain and everything to lose from sending out a short e-mail pointing out that someone's model doesn't work.
[0] https://www.reddit.com/r/todayilearned/comments/15m8om/til_c...
[1] https://www.businessinsider.com/susan-fiske-methodological-t...