True, but there's bad and there's bad. You might be correct that most of TOS was badly written, although a large enough chunk is well-written that I'm not sure where the balance lies. I *think* you're incorrect about TNG, but I'm going to find out shortly: the elliptical machine is supposed to arrive tomorrow, and I plan to begin to rewatch TNG from the beginning. My recollection is that Season 1 is unbearably awful, Season 2 starts to have some good episodes, and from Season 3 on it's pretty decent. We'll see if foggy memory matches current taste.

But I have to agree with the other reply -- bad was bad, even then. There's still plenty of bad today; it's just that most stuff of that quality dies in well-deserved obscurity. This particular example happened to live on to be remade, mostly because of its connection to The Great Bird of the Galaxy...