companies have legal duties to enforce code of conduct they established. It happened that Attlassian adapted freedom of speech in its code, and also likely non-retaliation policy, so there is some ground for law enforcement.
Not all jurisdictions respect freedom of association to the same degree.
Employment can be anywhere on a scale from a simple exchange of time for money, to something closer to a feudal lord/serf arrangement.
According to the now discontinued CIA world factbook, the US is a "republic with strong leaning democratic ties", the 2 worst institutions in the USA are school and work.
Both are increasingly fascistic and authoritarian. Both are approved to exist at the approval of the federal and state governments. But both throw out due process, all Bill of Rights, and more.
But the monied elite? Oh yeah, their rights are preserved. They DO get all their rights.
Is the first amendment really 'Freedom of Speech', if you're saying it while living under and interstate overpass?
And before someone says "The first amendment only applies to government", remember all companies must get the approval of the same government. The government should apply the same rights to any prospective corporation, being an extension of government.
What an uninformed take! That's why we have labor laws and such a thing as "wrongful termination" exists.