Well it did have to change its name from GAIM to Pidgin at some point because it infringed on "AIM" by AOL. And whether or not Pidgin was fully "TOS-compliant"

Well it did have to change its name from GAIM to Pidgin at some point because it infringed on "AIM" by AOL. And whether or not Pidgin was fully "TOS-compliant" (which it might have been depending on the service we'd be looking at) is not as relevant as whether these terms would have been actually legally enforceable or not.