One theory is that it's done intentionally to farm engagement from people pointing it out. Also I think most mainstream platforms heavily push down in the algorithm content that isn't sanitised. This is to make the platform more appealing to advertisers because the platform's userbase is the product.

As for why the words are partly censored instead of completely censored I'm not sure. I'd guess it's to game the algorithm while also making the word completely obvious.

Either way, if this is the behaviour that you engage in on a platform, that platform is terrible and you are an attention obsessed idiot.