This is a _community_, not a web app. Maybe the two words mean the same thing to people nowadays, but it didn't back in ~1999, when this community was formed--5 years before the website was formed. It's not the case that the website is the central hub for everything. As I said, players sometimes prefer coordinating over IRC or other mediums. And in some cases, there isn't one central place to play matches.
You can certainly mitigate the problem by encouraging people to use a web app to coordinate. Maybe there is an incentive structure that would help drive adoption. But whether or not people use the web app or not, they are still apart of the community and we have to serve them. I don't necessarily decide who is in and who is out.
Anyway, the point of my post wasn't to complain that there aren't workarounds. There are. I just think we as a society _shouldn't have to workaround DST_, and I wanted to add my lend my (largely insignificant) story to the cause.