For those people able to see colours.

So because some people are colorblind or just blind lets not do it. Great logic.

I think we should also disable voice calls. Some people are deaf.

Agreed. I also think we should remove the displays on phones. Some people are blind.

We should remove this thread because some people can't read. Goodbye internets :(

As opposed to currently giving no indication to anyone, colour-blind users included.

I think everyone can see colors, even color "blind" people. Those folks just have a hard time distinguishing between shades of particular colors.

I don't think anyone's literally living in greyscale.

there are but it is very rare and comes with drastically limited eye sight anyways.

Red/Green confusion is quite common though, there are estimates of up to 8% of ("western") males. Definitely a number to consider if you want your whatever to cater as many people on the market as possible.

The commoner kinds of red/green colorblindness, though, are by no means absolute. Most red/green colorblind men can tell highly saturated reds and greens apart -- they only have difficulty with low-saturation refs and greens.

> there are but it is very rare and comes with drastically limited eye sight anyways.

As one of those very rare individuals you allude to (see everything in greyscale), you should be aware that my eyesight (and many people with a similar condition to me) is "limited" but not to the point where i can't cross the street or need to use a screen reader.

Having said that, even for me knowing the colour would be useful even if I can't exactly distinguish it (e.g. I'm waiting for a white station wagon, its definitely not that black hatchback that slowed down in front of me)