How to become a member in Stream Public group?

We have recently started using Stream as the company video portal and the following question has popped up, I have tried to look at a wealthy amount of documentation and videos but haven't really found an answer for this.

So the question, if we create a Public Group in Stream it states in Stream documentation

Characteristics of a public groups:

• Anyone in your company can join without being added by a group owner.

How does on then become a member of that Public group?

• There is no Join button visible in Stream
• You either need to find your way into the SharePoint site of that Office365 or by searching the Group in Outlook (in our tenant we have disabled the visibility of Office365 Groups in Outlook so this is a bit difficult to explain)
• But since for example you can easily join Public groups from example Microsoft Teams, why is it so hard to do this in Stream?
• Or am I just missing some point that isn't documented anywhere properly

And yes I know a Company wide Channel might do the same purpose we have here, but we have some amount of Public Groups already available so using those is an option we are exploring.