If demonstrable harm is your standard, please just announce you don't believe in free speech and move along. Everybody advocating for the wrong stance on politics creates demonstrable harm.
Free speech means he can say (edit) legally protegted speech* on his own platform.
No company is obligated to provide that platform for him. When judging a company for what content they decide they don't want to host, spinning "vimeo banned Alex Jones" as negative is ridiculous.
Edited: he can't actually say whatever he wants even on his own platform. There's actually a lawsuit against him right now. Too many internet folk don't actually know what "free speech" means and I should not validate such ignorance.
Actually, free speech is an ethical concept, not a legal concept. The first amendment is a legal concept. Free speech means means enabling the free exchange of ideas. Free speeches as a concept applies to private platforms and organizations too, it just isn't mandated by law.