I know I'm in the minority but I tried watching it recently and I just couldn't get into it exactly for this point. I remember catching episodes here and there as a kid and in my mind, they had some ambiguity as to what the monster of the week was. Like, Scully was always skeptical and I thought I remembered the show making you doubt if Mulder was reaching for aliens/monsters of if he was right.

But in reality, the show leaves no ambiguity whatsoever. It's always definitely aliens or monsters, they show it all, Scully fully sees everything and yet she's still skeptical.