I call those systems "auto-censorship".

They are as dumb and undesirable as incomplete regex email filters in web forms.

Every single one ever written will have this problem. And ironically, absolutely nobody reading a fart joke will ever be offended. But the millions of people who are denied service and not twitter famous enough to reach a dot-com employee are very much offended.

...Also, the single reason to add those auto-censorship features is to please advertisers, not to protect users/drivers from fart jokes.

Expect Advertisement on lyft very, very soon.