This isn't remotely apples to apples; for example, HN has zero avatars, Xenforo has zero avatars, whereas Discourse shows up to five avatars per topic, of which

This isn't remotely apples to apples; for example, HN has zero avatars, Xenforo has zero avatars, whereas Discourse shows up to five avatars per topic, of which there are many on the homepage. I'm unclear where you are getting 3.2MB from, since sorting by filesize, here are the largest network requests at meta.discourse.org: http://imgur.com/8v4Fp4L http://imgur.com/8v4Fp4L As you can see, starting at 11.5kb and below it's all images (avatars). I suppose you could try with images disabled. If you want to make a case that 'not showing avatars by default uses less bandwidth', then I guess I can agree with that. But these images won't affect actual load time, as images rez in later, and all the dimensions are set on the page.