I Know what you mean. Except for the disc brakes it reminds me of 1X conversion of a vintage steel MTB. Which isn’t a bad thing at all. I have a garage full. I never really thought the 650B tire size was that much of an advantage over a 26”. Still it is an interesting bike in a sea of AL and CF bikes.
I have a steel Salsa 29er that's setup rigid, and two Priorities running 650b wheels. I do like the 650b wheel size for the road plus application, but that's just my own body size and preference at work. The Jamis design is nice, and I like it a lot, but it would be too redundant with just those three bikes that I've listed. I do like it though. The Jamis would be a good style of bike where I live. You want something here that you can slam around a bit.