I don't know how to rate The X-Files. At it's peak: sublime character driven TV with many diverse takes on sci-fi and horror. I've always maintained the first movie is where the series should have concluded.
Did not conclude there however. Instead, we got season after season of extremely varying quality. Season 6 has a comedic emphasis for instance... who asked for that? X-Files just kept going, and kept getting worse. Look at how Scully was recently treated in Season 11. I couldn't even finish the entire series because of fatigue and lack of interest.
4 stars seems like a fair enough rating. Acknowledging the series' AMAZING first half and less than stellar second. The truth is not out there, but right here.