I think it's fair to say he would not have stepped down had this boycott not happened. Furthermore, the Board could have refused his resignation, saying, if you're stepping down because you believe you're a liability to the company, don't. Stay on and we'll work this out.

Perhaps that's actually what happened, and Eich chose to step down anyway. We'll probably never know. What we do know is that current trend of politicizing everything has reached a new milestone (and a new low).