I’m remembering this specifically from a UK point of view, but definitely was the case for US TV also.
In the 90s I used to watch The X Files, Strange But True?, Fortean TV, Eerie Indiana… GhostWatch was a one-off that unfortunately I missed at the time.
There might be a couple of other shows I’m forgetting…
But looking back it seems cool to me that mainstream TV was so into “weird” stuff back then.
Beyond Belief: Fact or Fiction was another great one, in this similar vein.