> You are ignoring the external costs of street parking and cruising.

I'm not ignoring them. I'm saying there is already a built-in pricing mechanism because cruising consumes the time of the person doing it, so they will want to minimize it and limit the amount of time they're willing to spend on it. If you have an area with minimal parking available then people who own cars will not be willing to live there because it will be too inconvenient to find parking every day, which thereby limits the amount of it that will happen.

> Those mandates exist for a reason, and your solution of just letting everyone build and do whatever they want does nothing to address this.

Sure it does, because the effect is a local phenomenon. People don't go cruising for parking spaces miles from where they want to be. So there can be areas with more parking and areas with less parking with all that each of those entails, and if you prefer the former then you live there and someone else who prefers the latter can live on a different block.

> bus lanes can be effective at reducing traffic congestion in many scenarios.

> https://www.vtpi.org/blw.pdf

This paper opens with an obvious fallacy:

> Bus lanes can carry more passengers than general traffic lanes, and
so increase total capacity (people per traffic lane)

As above, if traffic moves at 30MPH this is only true if there is a full bus more than twice a minute. Even if you assume traffic congestion so traffic only moves at 5MPH, you would still need a fully-loaded bus more than once every 3 minutes to carry as many passengers as a lane of single-occupancy cars. And less than 100% of cars are single-occupancy.

Moreover, it's even worse than that, because the bus doesn't cease to carry passengers when there is no bus lane. And a bus that comes on the same interval has the same carrying capacity whether it has its own lane or not.

The theory of the bus lane is that the bus will then be faster than driving and so more people will take the bus. But in order for this to actually move more people than a general travel lane, the incremental increase in bus ridership from the bus lane has to equal a full bus worth of passengers at the above intervals, because the passengers who take the bus either way are not a benefit attributable to the bus lane.

Bus lanes simply make no sense, because the number of riders you would need so that the incremental increase is that large is more than enough to justify a subway line. There are in fact widely used and sustainable subway lines with fewer passengers than that.

And it's worse than that, because the conversion of a lane to a bus lane increases congestion in the remaining lanes, lowering their carrying capacity, which that paper ignores:

> Travellers who shift from driving to transit in response to bus lanes are
generally better off overall (they gain consumer surplus), or they would not change mode

Not true if the bus lane increases travel time for non-buses, which is exactly why people object to them. (The paper is clearly an advocacy piece for bus lanes.)

> especially coming from someone who just said "the way to solve this is diversity".

If someone says that food diversity is good and you shouldn't mandate that everyone eat only french fries and they also say that cyanide is poisonous and you shouldn't eat that, you have not discovered an inconsistency.

> There is a major cost difference between building a bus lane and a subway.

It's not that the subway costs less to build than a bus lane. It's that the very high amount of ridership you need in order for a bus lane to increase passenger capacity is more than the amount you need to make a subway economical. And subways are superior in any place where they're economical because they don't consume space on the surface.

> Even Tokyo - which has arguably the best rail infrastructure of any city in the world - uses buses and dedicated bus lanes to expand coverage of public transportation where a subway line is not feasible or warranted.

Governments everywhere regularly do inefficient things.

Putting a bus lane somewhere that you can't economically put a subway will only wastefully reduce transport capacity because there won't be enough additional buses in it to compensate for the number of cars it could have carried in the alternative. The only place they "work" is in the places where subways work better.

> All forms of transportation - cars, taxis, trains, buses, bikes, walking, etc - have their own distinct advantages and disadvantages, and city planners need to consider all of the above when designing transportation infrastructure.

Different things have different advantages and disadvantages, but some things have no niche in which they have a net advantage over a known alternative. Bus lanes are wastefully inefficient in low or medium traffic areas and inferior to subways in high traffic areas, leaving them with nowhere to be.

> After all, we've had scooters and motorcycles for well over 100 years and they only make up a small fraction of automobile use.

But the same is true of bicycles. The question isn't whether ebikes will replace cars, it's whether they'll replace bicycles.

But putting ebikes in bike lanes is also a problem, because the rationale to have a bike lane instead of putting bikes on the sidewalk is the speed differential. And now you've got more of a speed differential between a 28MPH ebike and a 12MPH bicycle than you had between the bicycle and the pedestrians, and in a narrower space.

So the ebikes would need their own lane, but that would only increase ridership by the number of people who don't feel comfortable riding in traffic, which are unlikely to be enough to justify the separate lane, because as you point out, two-wheeled vehicles as a whole are a small fraction of vehicle traffic.

> I also disagree that charging for street parking or utilizing the space more efficiently would disproportionately hurt the poor. If public transportation could be improved as a result, then that could be a great benefit to the poor (many of whom cannot afford to own a car in the first place).

You're conflating two different things. The point was that if you charge for it, it hurts the poor because now they have to pay. In that case the street parking is still there and you can't use it for something else.