Perhaps because you are expecting it to be something it is not (a Triumph). If you can figure out a way to let go of that preconceived expectation, you will be able to experience the bike with l ess bias/baggage. It sounds like you are clinging to something for now, and that will cloud your experience.I just cannot seem to get the buzz I had from my previous (Triumph Bonneville) bike.
Kind of like having two kids and expecting kid 2 to live up to the expectations of kid 1. Or Kid 1 not living up to expectations in general, thereby not seeing their unique and special qualities in the first place.
You said it yourself
It does indeed have all of these qualities when looked at objectively.it is in amazing condition, it handles beautifully, it sounds great and it looks fantastic
It is a fantastic machine that a lot of people poured their blood, sweat and tears into producing as best they could, but it is not a Triumph. So it is not really fair to hold it to that standard. It has it's own spirit (as much as an inanimate machine can have "spirit").
But if you're looking for a little scrappy British bike, the R9T is not going to provide. It's a Big Bavarian Bull of a bike.
Good thing is, with spring/summer coming it should be easy to sell.