I think that's Paul Verhoeven's fault. He doesn't understand the difference between satire and farce.
In a farce, the world the characters inhabit is entirely different to our own. In Airplane!, the characters are deadly serious, but the world and culture they inhabit is 1000% sillier than ours. You don't watch Airplane! and come out of the theater thinking "man, air travel is the stupidest thing we could be doing, it's time for anti-aviation social reform." You spent your evening laughing at the ridiculousness of it all.
Compare that to Dr. Strangelove, which is also over the top ridiculous, but it has some serious and sane characters in it to help ground the satire. There's a theme where the higher in rank a character is, the more crazy they are. The crew of the bomber, enlisted through lieutenant, are perfectly professional. Captain Mandrake is the movie's straight man. Major Kong is a bit of a character but he takes his job seriously. Colonel Guano is checked out, General Ripper is elbow chewing insane, and The War Room is full of nutcases. The grounding in reality provided by the straight characters who respond realistically to the situation is what makes the satire effective.
Paul Verhoeven doesn't let any normalcy into his movies. I think Showgirls is the worst for it because it doesn't take place in a Sci-Fi future, it's supposed to be the film's present day...except people don't talk like that. People don't act like that. Sex doesn't look like that. Vegas doesn't work like that. So, this movie isn't set in our reality. The closest thing the audience is familiar with to what's actually on screen is a Skinemax flick. People don't act like that and sex doesn't look like that but the actress really took her clothes off, so...am I supposed to be whacking it right now? Metallica managed to get the point across more effectively in their music video for their cover of Turn The Page than Verhoeven did with a $45 million feature film.