Depends on the bike, I think. Most cars on the road today are well-suited enough for both short and long distance travel. While there are surely some motorcycles that are good for both, there are a much higher proprotion that are better for a specific type of riding, to the relative exclusion of others - whether that be for reasons of ergonomics, curb weight, cargo capacity, handling and suspension comfort, etc.
I dunno. Highway hypnosis is much more likely on well, a highway. Folks will be paying a lot less attention in that scenario. Hell, even you will likely be paying a lot less attention. It's just how humans work. Monotony breeds complacency. I understand your reasoning for think the motorcycle is safer on the highway than in a heavily traffic urban area. But I do not understand why you think it's safer than the car on a highway.
It's very easy to retain a safe zone and avoid bullshit riding on a highway. The worst that happens is people trying to merge into you, but it's not at all bad because it's very easy to just keep space alongside or power out ahead. Riding on the highway is very pleasurable. It can be a lot more stressful in the car, especially as traffic thickens.
Speed is a much higher contributor to motorcycle casualties, but getting slammed into on blind corners, intersections, etc on normal roads is where most of the shit happens. Riding of highways in bad traffic can physically/mentally exhaust me because I'm frequently very tense and alert.
I don't understand why it's more stressful in a car than a motorcycle, especially as traffic thickens as that would make the situation more dangerous. Like, are you saying you wouldn't be tense and alert on a motorcycle in bad traffic on a highway?
Because, in a car, it's a lot harder to get out of shit going down on the highway. Pile ups, blind merges, etc. On a bike it's easy to give yourself all the space and time to evade and keep going while carnage ensues in the mirrors. Most of the time you just use the shoulder to go around or pull up safely away from it all. Bikes are real easy to do evasive maneuvers on, whereas trying in a car usually results in people spinning or going sideways. You don't often emergency brake riding on a highway, it's usually just going to where the cars aren't fucking up and powering away if needed. Still stop though just in case something had happened or need to share helmet cam footage.
In my country, the majority of motorcycle casualties not involving the rider being at fault, are intersections and motorists failing to give way. Almost all over highway speed are single-vehicle, so just the motorcyclist likely being reckless/speeding.
You keep saying the problematic times for motorcycles are the same problematic times for cars. I mean, there's still no statistic to even back your claim other than a feeling plus a really overly defined and restrictive scenario that doesn't exist in the real world. All highways have merges. And cars can just slam into a motorcycle without warning if they don't see them. It's one of the main causes of accidents.
Don't assume statistics are made up, "feels", or non-existent when someone uses them. My statistics are from a research publication on national motorcycle safety by one of the world's top universities here, though it's not hard to look up the stats which is their base data for the publication. Which is why I also did that with publicly released statistics and insights from a state government's road department—which obviously say the same tjing, but always go with two sources just in case. I only bothered to do that to load on top of my aforementioned experience as a long-distance rider and driver, but obviously it's silly to just go with that if I want to avoid some idiot online, because my own 12 years riding wouldn't be enough. You'd note I also kept reference to my part of the world as that's where the statistics and my experience are from and I can't speak for every country or state, especially those with outlier regulation that may see statistics that are higher or lower outliers to one of arithmetic means.
And, obviously, it also refutes your outlandish claim that being merged into on a highway is one of the main causes of accidents. To explain how stupid that is to a non-rider is futile. If you are a rider—holy shit that's a concern—stop. You shouldn't be allowed on public roads if cars merging toward you is stressful or challenging. Fuck knows what'll happen when you have to do a U-turn, switch directions counter-steerimg, or deal with compression lock from downgearing way too prematurely—the basics.
What stats? You didn't provide any. And I was repeating your claim about merging on a highway. You said it was the only real issue. What the fuck is going on?