I'm not understanding your categories. Every dictionary word is flagged? It seems any first or last name is a "public_figure" ("apple" is a "public_figure" and also a "brand", I guess that means there's someone named Apple? Tim Apple?)?

It "blocks profanity", but "shithead", "assfucker", etc. are allowed (not to mention obfuscating a restricted term even slightly, e.g. "sh1t")? Yes, the Scunthorpe problem exists, but you can do better, and should if you're expecting people to pay to wait 500ms.

Something that detects these sorts of things very well could actually be worth paying for, although it still would probably be better off as a library.