The whole post 9/11 thing is a part, I think, of what made me shy away from Enterprise
when it debuted. It just made everything about the show 'feel' more wrong than it probably was. I'd sample an episode from time to time...but by the end of season 2, the Xindi attack just sort of brought brought back the idea that the series, as well as the real world, was just drifting away from anything which felt "right" to me.
I always wonder why shows do this. Contemporary references always
become dated, like when some program or movie makes some allusion to, say, O.J. Simpson. "Gee, I wonder when this came out?".
I've mellowed since, and can watch the show without a problem. It did surprise me, though, that in the wrap-up of the Temporal Cold War (when time was re-setting itself), that among the historical images was one of the smouldering twin towers.