This is way overblown. It's not backstabbing or lying to change your mind.

The founders probably had the intent to stay independent, they changed their minds.

The employees got a salary to work on a mass email product. Now they are continuing to do the same.

This is just normal business, not a shift in principles.

If they were working at a public green energy foundation dedicated to open source science, and then were bought by Exxon and everything privatized, then this would be a different story.

I'll bet most employees don't really care that much as long as they keep their jobs and working conditions.