“Free” is a simplification. Bad actors can hurt lemmy - however it is also easier for the individual to fight back. If an instance acts unfairly, an individual can choose to ignore that instance and not lose all of Lemmy - they would still have access to all other instances.

For those that need an answer. You can fix the message by unsubscribing and subscribing from the individual community page. It won’t work from the Communities listing page

It is Facebook Meta. The why is harder. I guess they want a piece of the Reddit pie, or want to take over the fediverse.