If Matt thinks he has a legitimate trademark claim, file it in court, don't play games with 3.5 million WordPress end-users that are now cut off from security updates -- including all users of the ACF plugin that aren't even WPE customers. This blog post did nothing to explain the logic behind Matt's actions (and shifting explanations for them). The only convincing sounding explanations I've found have been on Twitter, and they all revolve around WP's stagnation and Automattic's market weakness, not anything WPE has done, and nothing that will end if WPE pays the extortion demands.