Okay, so you're talking about an additional premium/first class bus service, rather than a change to the existing service? I suspect that that is doomed, because class-segregated intraurban transport _used to be a thing_ (albeit largely on metro and commuter train services, not buses), and it's died out virtually everywhere in the world; when offered the choice of paying X or 3X for the same journey with better seating, people just don't want to do that for short journeys.
For instance the Paris Metro system used to have a first class carriage, until I think the late 80s.
And this would actually be worse, because you'd be talking about separate, likely less frequent buses. Most people will just get on the first thing that comes along, unless it's more expensive.
In general, on transport, people will pay a premium for speed; _express_ bus routes can charge a premium. For instance going to the airport I can take the city bus system for 2 euro and take over an hour (I'm on the wrong side of the city) or an express service that takes 20 minutes but costs 8 euro. I take the express one, and so do enough other people that it stays in business. And they'll pay for better seating for _long_ journeys. But 'long' appears to mean "at least an hour" and possibly "at least two hours".
(Semi-anecdotal evidence of this; in Ireland, a small country where most rail journeys not involving a transfer are <2 hours, first class _used_ to be a thing on trains, but it has been withdrawn from all services except Dublin-Belfast (2 hours) and Dublin-Cork (2.5 hours) because people simply weren't using it. You also see this with air travel; non-budget airlines have been cutting non-economy seating on short routes for years because it's hard to sell.)
It is an interesting mix of a private and public service. Mostly it is used by people who prefer a better ride experience than on a public bus. And are fine with paying a much higher price per ride. They pay out of their own pocket to the service provider, Volkswagen. But for people with disabilities, using the Moia buses is free and paid by the city.
> If we double the number of buses, we can increase the number of seats per bus and still have a higher overall passenger capacity in the city.
As mentioned, in a large bus system, the logistical challenges of doubling the number of buses would be formidable, and would likely lead to overall service degradation.
Are people paying for the _seats_, here, though, or for the more direct route? (AIUI it's a hybrid bus-taxi sort of thing where it only stops where people have indicated they want to be dropped off/picked up on an app). Like, if it was all-seats but operated on a normal bus route, I doubt people would pay for it.
I'd also question how sustainable it is; as far as I can see it's basically an experiment by VW, and likely a subsidised one. It feels like one of these things being prepped in case self-driving vehicles ever work properly. And in any case the scale is _tiny_; apparently a ridership of 11 million ever.
I think that there's a practical upper limit for most cities (it'll vary somewhat depending on population, road layout, openness to measures like making significant parts of the road network bus only, etc), and that most cities do tend towards more or less hitting it, yeah. Adding bus capacity is a cheap option up to a point, but there are _limits_, and as you hit those limits you generally explore expensive higher capacity options for busy routes (in rough order of expensiveness and capacity these tend to go BRT -> tram -> commuter rail -> metro).
This is a simplification, and there's definitely wiggle room within those categories (for instance, there exist tram lines which are higher capacity than many metro lines, mostly through the use of extremely long tramsets) but _basically_ how it works; buses can only take you so far, capacity-wise.
For instance the Paris Metro system used to have a first class carriage, until I think the late 80s.
And this would actually be worse, because you'd be talking about separate, likely less frequent buses. Most people will just get on the first thing that comes along, unless it's more expensive.
In general, on transport, people will pay a premium for speed; _express_ bus routes can charge a premium. For instance going to the airport I can take the city bus system for 2 euro and take over an hour (I'm on the wrong side of the city) or an express service that takes 20 minutes but costs 8 euro. I take the express one, and so do enough other people that it stays in business. And they'll pay for better seating for _long_ journeys. But 'long' appears to mean "at least an hour" and possibly "at least two hours".
(Semi-anecdotal evidence of this; in Ireland, a small country where most rail journeys not involving a transfer are <2 hours, first class _used_ to be a thing on trains, but it has been withdrawn from all services except Dublin-Belfast (2 hours) and Dublin-Cork (2.5 hours) because people simply weren't using it. You also see this with air travel; non-budget airlines have been cutting non-economy seating on short routes for years because it's hard to sell.)