I read the first third-party piece about this and nothing sounded outrageous. Read Jason and DHH's pieces, and then DHH's follow-up entry. I read Jane Yang's bit. And I read some Twitter threads from employees.
Obviously employees are well within their rights to want a workplace where they form HR policy and the founders can want another scenario if they think it's to the detriment of their product. Former can move on to another workplace. Founders can wear the blowback of their decision.
eg. if Basecamp got bulk gym memberships at 20$/employee but each employee would have to sign up at 40$ per person, Basecamp paying each employee 20$ would not be the same as giving each employee a gym membership.
Fair enough that it might not work so well in subsequent years due to taxes.
If it was purely about talking about politics at work then everyone wouldn't have resigned.