It's funny. I love watching old sitcoms, and I've been watching Threes Company for the last week or two, which is essentially the 1977 version of that show. From what I've seen and heard about 2BG, nothing about that show would amuse me. Threes Company was actually somewhat funny. Good writers have known for centuries that while well placed crudity can be good for a huge laugh here and there, it's cheap and easy to overdo. Innuendo is what works for the big picture. It just requires a less lazy audience, willing to look for the humor rather than being dick-slapped by it.
And add to that, Threes Company had better T&A, for much the same reason.