Ok I really have to say something. I hope those standards you apply to Frasier are being applied to all the sitcoms you watch on television today...
1. The characters on Frasier (particularly the male ones) are heightened and their behavioral shortcomings are played in such a way that they become the butt of the joke. Not only is Bulldog is fired multiple times for his behavior, but the women on the show end up having the power over him and slapping him down. Taking his toxic masculinity and making him regret it. From Daphne to Roz to Mercedes Ruehl's character, Bulldog always pays for his behavior. That's the joke.
2. Again, the ones who often "slut-shame" Roz are the men who act the same way, and the show makes THEM the butt of the joke, not Roz. Frasier sleeps around, Bulldog sleeps around, Martin sleeps around. But in the end, Roz always ends up with the wisdom and confidence while the men look like idiots. (By the way, Modern Family treats the character of Haley Dunphy way worse then the Frasier series treated Roz.)
3. The joke of Nigel is that Daphne is oblivious. The joke is on her, not Nigel. She mentions so matter of factly that Nigel used to watch her brother in the shower, not her and teaches ballroom dance and met his "friend" in prison, but doesn't seem to "get" what that means. It's not that anyone is supposed to care Nigel is gay, but that Daphne is oblivious not only about Niles, but about other people she loves.
4. Gil is in the closet. The joke is not that he is gay, it's that he is so OBVIOUSLY in the closet. No one is judging his sexuality. Will and Grace, Modern Family-- they all made the same joke, with characters much less three dimensional than Gil.
"I shall stay until the wind changes."
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