WP Engine is no different from the million hostings that auto-install WordPress and “abuse” their resources.
Worth adding that WPE is owned by private equity, and they allegedly tried to remove the newsfeed from wp-admin to hide his (dramatic) posts about them
so then the question becomes "Why is the Foundation/project hamstringing a competitor to their director's for profit company who is, in theory, and legally should be, independent?"
I'm guessing you are not size of WP Engine and Silver Lake, honest question, if you were, would you want to contribute back to WordPress?
Suppose one of your developers writes on twitter that you don't permit contribution, and you fire that developer on the next day. What reaction do you expect from the people who pay for most of the development?