I think most would agree more professionalism would be nice, in fact getting rid of a list of funny customer names (as employees suggested) would be more professional, not less. But again, that's not really what the core disagreement is here - that's not IMO why people are quitting - it sounds like most of the company agrees that is a good idea.
They are quitting because the founders decided to assert their power nakedly and without restraint, to berate employees, shut down their organisation and discussions and attempt to dictate terms to them in a humiliating public way, that is to break the social contract between employee and employed. In doing that they declared that they alone decide the rules, they alone decide what is acceptable to say and what is not.
Every workplace has some subtle set of rules about behaviour but these rules are negotiated between employer and employee, and if as a manager you lose sight of that, you'll lose your best employees as they decide they don't really want you to decide everything about their waking hours without consulting you.
They are quitting because the founders decided to assert their power nakedly and without restraint, to berate employees, shut down their organisation and discussions and attempt to dictate terms to them in a humiliating public way, that is to break the social contract between employee and employed. In doing that they declared that they alone decide the rules, they alone decide what is acceptable to say and what is not.
Every workplace has some subtle set of rules about behaviour but these rules are negotiated between employer and employee, and if as a manager you lose sight of that, you'll lose your best employees as they decide they don't really want you to decide everything about their waking hours without consulting you.