Yes and no, Enterprise was starting to get good when it got cancelled.
The problem I always had with Star Trek was it's high gold to cr*p ratio. For every "City on the Edge of Forever" type episode which blew you away, you'd pay for it with a ridiculous episode about space hippies or the like. This pattern occured to a greater or lesser extent on all of the Star Trek series.
Compare this to a show like Babylon 5 which had less "great" episodes, but which was consistantly "good". (I can't think of a B5 ep which was a true stinker).
Nevertheless, the Star Trek universe has so much depth to it that I would love to see a new series in a few years.
I think the reason for that was that B5 had a story arc by Straczynski. The series had a direction to go in and most episodes were important on that path. Even if someone else wrote the episode, Straczynski was involved. Compare that to Star Trek where it seemed that all the everything had to be reset to its original condition at the end of every episode. Sure you could kill off a red shirt or two, but you never saw them before the episode and never would have seen them later anyway. You could play Star Trek in any order and they would make just as much sense. If you get B5 episodes out of order you might go mad.
B5's biggest problem was the season 4/5 crash, where it looked like there wouldn't be a season 5. Thus the story had to be crammed into the end of season 4.
Herbert!
The Original Star Trek series wasn't quite socialist tripe. If you notice, even the space hippied episode had the space hippies die at the end from their foolish and impatient idealism. It had episodes that were pro-Vietnam intervention, pro-life, anti-collectivism, and so on. It's anti-racism episode showed the racism as a two-sided problem and at least two episodes had themes that children require adult supervision, which is quite far from the clever kid themes so common now. Basically, the still-conservative values of the mid-1960s moderated the show quite a bit and it was actually pretty conservative.
Compare this to a show like Babylon 5 which had less "great" episodes, but which was consistantly "good". (I can't think of a B5 ep which was a true stinker).
If you really want to see some socialist tripe, see the first season Babylon 5 episode, "By Any Means Necessary", a love letter to organized labor. Yes, the "Rush Act" is meant to mock Rush Limbaugh. To top it off, it's badly written with a straw-man villain and laughingly heroic labor union workers. There were some other awful first season episodes, like "TKO". And let's be honest, the fifth season wasn't necessary. I do think Babylon 5 was consistently good, but it wasn't stinker free.