I hear this argument a lot and partly I agree, but partly I disagree.

It's still your asshole, it's never going to be clean. Sure it might be clean after using the bidet (if you use soap) or if you use the shower (you do clean your ass in the shower, right chat?). But it's not going to stay clean, your asshole isn't some hermetically sealed airlock. Bacteria are going to leak out. People also fart all the time, causing even more nasties to leak out.

So an asshole is never going to be a clean thing, that's why people don't mind cleaning it with just a bit of paper. Elsewhere on the body, people do try to keep clean (hopefully), so cleaning shit there with just some paper isn't good enough. Although there are so many people that don't wash their hands after using the bathroom and using a phone on the toilet is also pretty normal. And those disgusting people that keep their towels right above the toilet. So the standards might not be as high as I would hope.

Regardless, I still think bidets are a good thing. And people should use them. But the argument most used on the internet is a bit flawed.