You would have to be a complete idiot to try and build your revenue on something owned by Twitter. They will shut you down at any time, for any reason, with no recourse.
In the new era of monopolistic common carrier platforms, you have to BUILD INTO YOUR BUSINESS PLAN what happens when you get screwed by, say, the Apple App Store, YouTube, or Twitter, et. al. It's a business risk, just like fire or flood. You have to have a contingency ready to go at a moment's notice. By example, Parler didn't.
With Revue and Substack, do the authors have access to subscriber email addresses? If so, that would somewhat blunt concerns like this, both directly (if you are booted off the platform) and indirectly (presumably the platforms would be less aggressive in their rules/enforcement if it is easy for authors to leave).