They are probably highly skilled in the things they are selected for skill in. “Smart”, even when it is really high general IQ, doesn't translate to universal proficiency without dedicating time and effort to particular domains.
> how can they believe in something this plain wrong?
Strong selective pressure: people who don't have beliefs that fit with the current Google context and bureaucracy are less likely to be selected by, or select to work for, Google and, even if they are, are more likely to be selected out, or voluntarily depart.
See the destruction of the Ethical AI unit over issues very closely related to the conflict over blind faith in algorithmic approaches.
I suspect the rationale is something like "Well, you don't pay for your YouTube account (or don't pay that much) so you shouldn't expect good support or moderation."
they are smart enough to know that "improved customer service" will never get them that promotion
The System constructed by Googlers is so smart, the Googlers themselves are subject to a form of papal infallibility.
Googlers are smart people, how can they believe in something this plain wrong?