The format is also used for races, you ride as quickly as possible and can only rely on commercial services available to all for resupply and lodging, no prearranged or private support.
This last summer I left my front door in the PNW and road 800 miles on a mixture of terrains to the tour divide, road 300 miles of that, then road another 1500 miles of pavement to Iowa. I'd call that bikepacking, and by my previous assertion it's also touring too. Not all touring is bikepacking, but all bikepacking is also touring. That trip is a good counter example of why it gets silly to define bikepacking by the terrain type.
/s
It can be simplified into a "saddle bag" vs "paniers", but IMO this is just a symptom. A form folows function. If You need to carry a full tent, sleeping bag and a change of clothes, touring paniers and heavy frame are probably the only way to go.
If You can cut down on comfort (or are optimizing for speed over long distance), suddenly You're left with a whole lot of options on how to carry whatever's left and You can use much lighter frame to do so.
Touring vs bikepacking being distinct I think is an anglicism, an americanization and a commercialization of the terms. The Americanization part I believe is "Bike Tour" being mistaken for in-contrast to "Car Tourist". "Bike tour" has nothing to do with "Car Tourism" or "Bike tourist". It is not short for 'tourist', which is where the americanization comes in. The etymology is French.
Take a look at my counter-example - was that a tour, or a bikepacking? It was 50% pavement. Meanwhile 300 miles was on one of the worlds most famous bikepacking route. These distinctions based on how minimalist of what you carry or where you go make no sense. Given that example, the most consistent answer is clearly "both". It was a bikepacking trip - I was carrying what I would have were I backpacking, while on a bike. Because all bikepacking is touring, it was therefore also a tour. Had I stayed in hotels/hostels and/or with & friends every night (not carrying everything I needed), then it would have been touring and not bikepacking.
We can look to the etymology of the words. 'tour' comes from French. You can do a "tour a pied" (on foot), "tour a velo" (by bike), or "tour a voiture" (by car). Because cycling is the national sport of France, "un tour" is understood to often be by bike, it's just shortened. Bike tour comes from that etymology, it is a superset. A bike tour might include a 'backpack' (bags), or it may not.
Language does evolve. The "current" anglicized understanding is silly though and contradictory. It's also way more commercial than I'd like.
Sorry.. I once spent a solid 7 hours thinking about the difference of touring vs bikepacking while on a bikepacking race. I had some time to really dig into it... I kinda dislike that 'bikepacking' is thought to be something apart from touring (and only in mountains, only on dirt, only with inline bags)- when instead bikepacking is just a subset of bike travel, bike touring.
I might have mixed up the subset/superset terms. Bikepacking is a subset of touring. All bikepacking is also touring.
In the UK we still have the Cycle Touring Club[1] which was founded in 1878, so it goes way back.
I don't even think there was originally much difference in the type of bags used. Really old school riders here used to use big saddle bags like those made by Carradice before panniers came into fashion.
I think I'm good with either term. All these amazing adventure stories make me long for summer again.
1. Recently renamed by some genius to Cycling UK (not to be confused with British Cycling which covers racing), still not sure why they bothered.
A couple years ago, my wife and I thru-hiked the Long Trail. We looked pretty hard at taking a bus to the start, but couldn't come up with an itinerary that took less than two days. Her parents ended up both driving us to the start and spotting our car at the finish. The finish is in the middle of goddamn nowhere; the start is near a fairly large city in western MA. It sure seemed like it should've been easier.
For our honeymoon, we did a couple hundred miles of the Northern Forest Canoe Trail. The nearest place to the start to return a rented vehicle of any sort was a neighborhood U-haul (as in, not a corporate location; think a gas station with a couple trucks). And then we still needed a 1 1/2 hour shuttle ride to Old Forge. We spotted our car to the end of the trip and threw our boat in the back of the truck to get to the start.
Usually away from cars, but not typically easy. Sometimes it feels like pushing a shopping cart over a mountain.