In one of the previous discussions, I linked to Charta 77. These guys did the same thing - they took the Czechoslovak government for the word that it respects human rights, because it was a signatory of some human rights agreements. They were persecuted.
The same problem you have with tenure. You are saying professors are protected with tenure, but are they really? Unless someone tests the boundaries, then you don't know if it really protects you. So assuming tenure will protect you is, likewise, a dangerous assumption.
Addendum: I would also like to point out this excellent book: https://www.amazon.com/Mistakes-Were-Made-But-Not/dp/1491514... That's why Google cannot change its mind even if it wanted to, sadly.
I'm just observing it's extremely naive to believe that a solicitation for feedback in an employment setting is somehow an invitation to free speech.
I wasn't implying you did.
> solicitation for feedback in an employment setting is somehow an invitation to free speech
Without further qualification, in a literal sense, it is "invitation to free speech". That's the problem.
"The society you live in" and "a basic understanding of how the world works" are always that most important qualifications on any invitation to share your opinion.