For no reason I can give you the finger, scream obscenities at you, and there are no legal ramifications.

Was I wrong?

The legal side is not the end all.

Otherwise, why is anyone complaining about Meta's data mining? About the cost of epipens?

In fact, Mullenweg says WP Engine does contribute back, but not enough, and tries to justify it by saying they've "hacked up" WordPress. The latter statement has no legs to stand on (at least without real evidence). How much is enough? Should WP Engine be fixing bugs that don't affect their customers? Exerting influence by throwing contributors at wordpress to make upstream improvements that benefit WP Engine customers? I suspect if WP Engine did what Mullenweg is indirectly demanding, we'd get a "no not like that!" post.

My example also cited two non-life threatening issues, and discussed legal vs morality.

You have not addressed this point, so I'll be more direct about it. Doing something legal doesn't make it OK. In fact doing something legal does not imply right or wrong.

WP Engine has been the top sponsor of all WordCamps for years.