I've seen some people defending him for various reasons, most prominently because he has a right to free speech. Of course he has a right to free speech, and he exercised it. He also has the responsibility to accept the consequences. His actions/speech made enough people angry enough to exercise their speech to the extent that Eich's position was no longer tenable.

People too often forget that rights don't mean that there will be no consequences to exercising those rights (within the bounds of the law, and other things).