Then you are optimizing for a minority of your audience and alienating the majority, all for a shade of gray. Readability should never be compromised.
edit: And before this is perceived as me being hostile rather than my intention of helpful (though it seems it already has), let me say that this is the kind of site I have been looking for. And thus I want to use it and want it to succeed. But certain design decisions can imply things to users that may not be intended. Content that is difficult to read, especially content which calls for interaction, does the opposite of what its intended for. And that makes users feel as if they're not wanted.
I think here's where the difference would apply. Designers almost all of them use high resolution displays. And maybe Designer News is aimed at those designers, who're at the cutting edge.
Do you really think "almost all" designers use a specific model of a specific computer that shipped about six months ago? Hell, I consider myself a half-assed designer and won't upgrade to a retina MBP because a) the screens have issues b) the web has issues and c) most of the design software I use has issues.
Designing websites in a way that only works well on retina displays has to be one of the most ridiculous examples of the Silicon Valley bubble in recent memory.
edit: And before this is perceived as me being hostile rather than my intention of helpful (though it seems it already has), let me say that this is the kind of site I have been looking for. And thus I want to use it and want it to succeed. But certain design decisions can imply things to users that may not be intended. Content that is difficult to read, especially content which calls for interaction, does the opposite of what its intended for. And that makes users feel as if they're not wanted.