….
So here's another honest question: Since flat bars are kosher, what's to stop me from calling this SL a gravel bike? Geometry?
nothing of course ! but i’d say the manufacturer’s intent (which does telegraph in lots of small decisions about the bike, as well as bigger ones like geometry) matters. the vado SL (and non-electric cousin sirrus, which we have a nice example of) is marketed as a fitness bike, or hybrid, depending on what time you look at the marketing lol. i think that’s a good category for it, it does many things pretty well and is of the most benefit to riders interested in fitness, varied surfaces (hybrid), and not racing.
i think the categories are pretty clear, even if some bikes meet criteria of multiples categories. road bikes (endurance or race) are made for going fast and far on paved surfaces. gravel bikes are made for going fast and far on unpaved roads. the various types of mountain bikes are for riding off road, on steep surfaces (aka mountains.)
as jeremy had stated elsewhere, there is absolutely nothing wrong with a bike that is pretty good at multiple things. i personally prefer focusing on one thing, which is going as far and fast as i can on the many beautiful roads within riding distance of my front door, so i like road bikes and find no benefit whatsoever to things like suspension, upright riding position, tons of bosses, dropper posts, 1x drivetrains, huge tires or knobby tires and so on. but those things are awesome for other situations!
if one wanted to get pedantic, there’s probably a scoring rubric for “what kind of bike is this” in which enough of a certain number criteria from a category or attribute qualify it as a certain kind of bike. they have this for diseases, of which being addicted to bicycles may be one!