Yea, the mistake encountered by the OP is that they were approaching the Time Machine UI with the intent of "I want to back up some folders". The TM UI is sole

Yea, the mistake encountered by the OP is that they were approaching the Time Machine UI with the intent of "I want to back up some folders". The TM UI is solely about recovery. It backs up "everything" not on the "skip list". And out of the box it defaults to just the system drive (vs the system and external drives). And that's an interesting facet here. This is a case of going in to a bookstore and scanning up and down the shelves and not finding what you want, and being frustrated, because you don't realize that you're simply in the wrong section. The TM UI in this case was frustrating because it had no options to do what the person wanted to do. And by design, it would not do what they wanted to do. It's not a UI fault of TM per se, specifically this aspect of the TM experience. TM excels at full drive recovery, and recovering "a few, select" files. In the middle, it's not so good. It's worked great for me. I've recovered from it several times, both entire systems and a few files. I use it solely on my main drive, and I use BackBlaze for the entirety of it all as a hat tip to offsite DR. Over the years, I've lost a couple of TM volumes to strange corruption. Not that much of a crisis, I just reset it and start over.