A great overview, but also some interesting tricks about permissions. I was also recently faced with the problem of how to find out if someone is a member of a particular AD group without the AD connector. If I had known this little workaround before, I would have done it exactly the same way. (Have it then solved via a flow query -> whether this person could query a specific list or not)
You can see this video here on my blog because I have rated this video with 5 stars in my Youtube video library. This video was automatically posted using PowerAutomate.