This is akin to the argument “Hey, if you haven’t broken any laws, you shouldn’t have any problem with the police stopping you in your car/in the street/detaining you for questioning/etc.”
The problem isn’t that some of us (probably most) wouldn’t love to stand by 100% of the choices we’ve made on the internet in anonymity. The problem is that doxxing is the internet equivalent of overzealous cops beating the shit out of you and then shooting you dead in “self-defense” after pulling you over because you looked high (and maybe were).
The internet is amazing for so many reasons, but one thing it’s really, really bad for is hysterical vigilantism. Connecting a handle with a real person and publicly identifying them is a serious threat, and accountability for acting like a poophead online is not the only nor the most damaging effect.