They are all private forums/Facebook groups for various YouTube analytics tools or production/business courses. So you would have to spend money to get access to them.

Thanks. Do you have any recommendations on ones that have been worth it?

Sure, https://morningfa.me/ (analytics tool) and https://incomeschool.com/project24/ (course) are both products that focus heavily on research based recommendations. Their YouTube channels (https://www.youtube.com/@Morningfame and https://www.youtube.com/@ChannelMakers) have a lot of good information as well.

They both have private communities where people freely share a lot of good info (especially Project24).

There are many others that I have heard good things about but have not checked out myself.