I have a special place for it for two reasons: As a young kid in the 70s, I could only choose from 4 or 5 channels on my little B&W set, and TOS was on one of the UHF channels opposite the evening crime/weather/sports blather that my parents generally watched on the living room TV; as I got older, I appreciated the characters, artistry, and intelligence of the series, especially in the first season. Most 70s and 80s shows were blown-dry and witless, but TOS showed smart, interesting people doing smart, interesting things -- and it wasn't a detriment to be so nor to associate with people of different races or back grounds.
By the time I was in high school, it was the Stallone/Cruise/Schwarzenneger era, where heroes all had to look like ridiculous action figures from some whitebread suburban nightmare of brandname shoes and designer jeans. TOS was still a bastion of sanity because as heroic as its characters were, by comparison they all seemed of human proportion, and as ridiculous as some of the later episodes were, the characters never seemed as ridiculous as some clown who seemed like he took steroids, worked out five hours a day, and could barely speak English.
People bash the special effects and aesthetics, but in doing so they generally lose sight of just how grounded the show was, even when it drifted into the sillier areas that were vogue in the late 60s. I never found anything in TOS any more ridiculous than the idea of some slow-moving guy as bulky as a professional wrestler getting shot at by 20 people and not taking a single hit while mowing everyone else down with a machinegun that magically never runs out of bullets. On the other hand, when Kirk looked weary, as though he suffered from the multitude of life-and-death decisions he made daily, and could vacillate between friendliness, irritation, and anger because of the pressure he was under and the stakes of the situation, I believed him as well as in him. I wasn't paying attention to the so-called cardboard sets because there was nothing cardboard about the people, nor the actors playing them, nor the scripts that often managed to be fun without dumbing anything down.
That era is gone, however. A few shows, like Southland and Law and Order, are of similar caliber, but even then, I too often find the ideas more compelling than the characters or actors who are playing them. Whatever magic that was a part of the 1950s and 60s is essentially gone, replaced mostly by flashier and more expensive dreck. Certainly TV sci-fi has gone that route.
