This is odd, I went to FQ and it shows Factual Questions all tags and is displaying All the threads not just ones with tags.
As I flip between all tags and no tags I see A question about early color television in both lists.
Even in Cafe Society all tags vs. no tags is working fine. British Dopers: Tell Me More About Christmas Pantos shows in both lists as an example.
Which interface are you using? I’m in Discourse Classic and will test a few others.