There is nothing troubling about this at all. WP.com is a paid service and they are choosing not to do business with this publisher. The WP ecosystem, of which WP.com is a very small part, is a robust market of ideas and it truly does, “democratize publishing.” Anyone who is claiming censorship, and de-platforming here is just revealing their ignorance.

This is WordPress, the content is portable. Move it and move on. Automattic staff helps with migrations all the time, and they do good work there. There is no conspiracy here, just a business decision and an operational obstacle that is easily overcome.