I know of several services that block traffic from Tor exit nodes including, as of a couple of months ago, the Australian Legal Information Institute. It's a sad state of affairs given that there are people whose countries block their access to information about the law of other nations and who try to use Tor to circumvent censorship, now only to find themselves stymied by the host that they are trying to reach.
I am familiar with the development by Tor researchers of means of circumventing censorship and giving access to Tor guards. Is there any similar development relating to the exit nodes? For example, one could envisage a changing series of hosts (a kind of "exit bridge" similar to existing bridges) that only accepted traffic from Tor exit nodes ... before passing the traffic on to intended sites.
Am I foolishly hopeful, or is the concept either (i) dead in the water for reasons that I can't envisage, or (ii) already developed?