Slightly greyer is OK, but if you give up most the contrast and use a small font, a large fraction of the population will find your site hard to read. There are way too many low-contrast web sites out there.

I have sometimes used slightly grey and used "full" black for small emphasis (when the bold version available for the font in use is a just too much or you want a level in between). On pages where other colours are used for highlighting things (links, call-outs, warnings, ...) it can also help them not look a bit more subtle than you want agaist the hard black.

You have to be very careful not to rely on it though: as you mention lighting and protection conditions or just plain bad monitors can kill the more subtle difference completely. And, more importantly, those with sight deficiencies might miss it even in ideal circumstances.

Yeah that's true. Cynically I think this problem will solve itself as millennials age.

Very true, however better has chosen #444 whereas #333 seems to work a bit more consistently.

One thing you should always consider during the requirements phase of a web application is whether your app is likely to be used projected on a conference room wall. Things like contrast and fonts make huge differences in such hostile settings, and available screen real estate is also considerably limited.

Great point yeah. I also think it should be easier to tell browsers to make text high contrast, design be damned. Fundamentally it's an accessibility issue.

Last time I was in this situation, the UX expert and I had the entire dev team stand at the back of a conference room and vote on which font was most legible. All but one agreed Verdana was the easiest. Not only that, but it was still more legible than our previous font at 1pt smaller text, which meant we could get more info onto the screen. Not tons more, but we were having to truncate text in some spots, and sometimes even one or two more letters is enough for people to get the gist without having to backseat drive the presenter. It's subtle but I was beginning to recognize this as an important waste of time and energy when we were dogfooding our app.

When people are already getting short with each other before you even get to the actual reason for the meeting, you know it's going to be a long day.

But corporate wanted our fonts to match their other product. I don't know if it was my imagination or not, but it felt like that act broke a couple people on the team, myself included.

Ooof that burns. Feels weird to have a UX expert but then ignore them? But of course, corporate knows best haha.