The original reason the Adventure bike segment was created was to ride long distances on pavement and then have enough off-road capability to go ride dirt in a far-away place. It's was supposed to be a dual-sport with street-manners so you're comfortable on the pavement getting to dirt.
Along the way it segmented alot.
1) We lost snotty little enduros, replaced by a Ninja or CBR with new plastics and 70/30 tires.
2) The unicorn is most likely hiding in the 650-800cc range somewhere around 400lbs.id argue the KLR was the first near unicorn, it was replaced by the Vstrom.
3) The carrier class, 1200+ behemoths, will remain the car equivalent of the Range Rover Defender.
Of course there are exceptions to how bikes are used, and niche brands that on paper and test track might be better - but the bike in a big markets bullseye will always be leaders in dependable and affordability .
That was always the original intent. Adventure TRAVEL. Ride a motorcycle across the roads of Morocco and then veer off into the Sahara Desert. No separate dirt bike involved. No trailering involved.
Perhaps, but it didn't take long for manufacturers to figure out there weren't enough riders interested in that type of adventuring on a motorcycle.
Turns out riders wanted a fat comfortable bike they could ride to the Sahara, take a selfie with their bike and some sand dunes in the background, then head over to Starbucks to share adventures with other riders.
But for riders like me, it would be amazing to have that one unicorn bike, which is both comfortable on and off-pavement. Not for the sake of owning just one bike, but to continuously travel on one without trailering or switching.
I believe the technology exists to create such a bike, but until now the market has been too small. However, as more people get into ADV bikes (as evidenced here on GTAM), I am convinced that eventually, these new riders will want to venture off the asphalt. And when they realize that what they've really bought is a street-bike in dirt bike clothing, they might go shopping for something more worthy of the name "dual-sport"....
I think that's wishing for a Transformer, not a Unicorn. Sadly I don't think you'll ever see that in a mass-production bike.
On a side note, I recently acquired a nearly new 1988 ADV bike, a DR BIG, that might be closer to the unicorn than anything available today. I'm having a ball riding it, my last fill-up was 530km ago and I just hit reserve. Can cruise all day at 130. Not as comfortable as a Vstrom, but with a new seat it would be close. 385lbs dry.
