I don't think so. I grew up watching Doctor Who on PBS, and then when I went back years later and watched them on DVD, the special effects looked pretty much the way I remember them. However, I am pretty sure that I wasn't watching the X-Files until about season 3, and it took a couple seasons before it became an "it" show, so it would make sense that the effects got better.
Although you do bring up a good idea for people to post on: shows that you fondly remember, only to rewatch them years later and you realize they suck. For me, that would have to be the Thundercats. As a wee lad, I obsessively watched that show. Then as a teenager, I watched an episode on Cartoon Network, and I was just like, "Was I really so stupid that I found this crap riveting?" By contrast, then and now I still like the original transformers cartoons.
"How is it that hardly any major religion has looked at science and concluded, 'This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant. God must be even greater than we dreamed'? Instead they say, 'No, no, no! My god is a little god, and I want him to stay that way.'" - Carl Sagan
"To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection." - Henri Poincaré