Yes I got that, but those emissions don't factor in manufacturing. I also told you why in the case of American cities they aren't effective forms of reducing emissions.

Did you even read what I wrote? Higher cab usage can lead to lower car ownership which means fewer cars manufactured. Manufacturing a car creates a lot of carbon emissions. In American cities, cabs seem to have mostly replaced transit trips rather than private vehicular trips. That's why you see the increase in carbon emissions. This is because our cities are so designed around cars that traveling by car, whether it is your own private vehicle or a cab, is much faster. Until that is changed, cars, whether private or taxi service, will continue to be the favored mode of transportation. All rideshare services did was lower the bar for traveling by car.

In dense areas, cabs travel quite short distances to their next customer, or they are simply hailed on the street itself as they drop off their customer.

Further, "efficiency" can mean a lot of things. Private automobiles spend most of their lives parked. Parking takes up a huge amount of space. "Sharing" a car through a taxi also means fewer cars need to exist, as the car is being constantly used instead of parked. This reduces the total number of cars needed in existence, which is efficient in another way.

The subway is just one way of getting around. The city has added tons of SBS lanes, more buses, bike lanes, and made the city safer for biking and walking in general. As we create safe alternatives people will switch to those

Maybe they will overtime.