Filter a view by the Group ID of the current logged in user
I just ran into this today. Found this article and here's the solution I did (only available recently).

I create Content view showing the Content Types that I want. I setup the Relationship to "Content group content" (checkmarking the Content Types I want). I then add a second Relationship to "Group" which is now available (based on the first relationship).

Once the relationships are done, I have access to add a new filter of Group ID.  I can manually enter a group ID number and it works... but current user has not been addressed yet.

Now I install:
https://www.drupal.org/project/token_views_filter
critically, with this patch:
https://www.drupal.org/project/token_views_filter/issues/3038695

I can go back into my Group ID filter and checkbox the "Use tokens".  Now I can access information about the current user via Tokens.

I felt like I should have been able to setup a Contextual Filter for this... but the system didn't allow for it, so this was my work around.