I'm not sure I understand what the life lesson is.
In my mind, the battle with the board should be "either we drop the evildoing sponsors or I quit", not "I want evildoing sponsors' money but I still want to retain the right to criticize them or I quit".
I was on the board of my own company, along with my partner, and an outsider. I learned the role of a board is to represent the interests of the shareholders. If the company CEO is publically undermining the company's partners, which may threaten the company's finances, the board MUST deal with the CEO. Telling the CEO to knock it off or resign was the correct approach in my decision. The CEO's role does not allow for speaking personal opinions that conflict with the company's overall health.
I Code Club's board for taking a stand, and respect her for resigning.
In my mind, the battle with the board should be "either we drop the evildoing sponsors or I quit", not "I want evildoing sponsors' money but I still want to retain the right to criticize them or I quit".