It's probably that I am through with big heavy bikes! I've had several K100, an Intruder 1400, even my beloved old XS650s I consider now as too heavy.
When I came across a XR650L because it was a good deal, and I rode it for weeks without riding any of the other bikes I had in the garage (up to seven) because it was so much fun, something happened. I slowly sold off the other bikes, the only new one was a DR650SE and a KLX250.
No more sexy looks, tons of power, exhausts of titanium, 180 rear tires, big twins, big four-cylinder engines; no more wide, heavy bikes that are difficult to handle in a parking lot. I never used them to their full potential anyways. It's better to ride the wheels off a smaller bike than to use only half of the potential of a big bike. Almost every time I opened up my ZX9R I got in trouble, either with traffic or the police.
Upright seating position, wide handle bar that keeps you in control, slim, light body and just enough power so you can drift out of corners - that's what I want!
Back to the topic: to me the 1200 Tenere seems like a bloated twin that took too many steroids. Too many designers adding on too many things.
A CB500X can go 180 km/h. I don't see the advantage of all that
mass. Maybe it's an image thing, why buy a cheap 500 when you can buy an expensive 1200?
That said, I'm sure there are people out there for whom a F800GS is too small or too weak or too light or too cheap; if they need a 1200cc bike that costs and arm and a leg and weighs three times their own body weight, fine, go ahead, buy it and enjoy it! To each their own.