[astura]

Ummm... Huh?

Taxis are a different color everywhere, there's no "standard," even NYC has green taxis ("Boro Taxis"). Yellow is a popular color, because it stands out, but I've taken taxis every color of the rainbow (well, maybe not pink or purple), each area or company is different.

In my neighborhood two companies operate taxis, one has a fleet of red taxis and another has a fleet of blue taxis. From my observation, black is probably the second most common taxi color.

You identify a taxi by it's markings, not it's color.

[beojan]

I wouldn't be surprised if users have inadvertently trained the AI behind reCAPTCHA to think all taxis are yellow.

[nurino]

Then it's not US-centrism but NYC-centrism?

I mean you tell me to check the markings, but you know in those captchas you can't see any markings because most things look like a blurry blob.

[astura]

Taxis are easy to identify - cars with a (usually lit) topper and writing all over them are taxis, the writing doesn't even have to be in a language you understand to be identifiable as a taxi - you don't need to actually be able to read the writing. Other marks like checkered patterns are common, taxis are designed to stand out.

New York City also has green taxis, so it's not anywhere-centric thing.