Imagine a small-town mayor who owns three shares of the local bank because her parents gave it to her as a graduation gift. She has no inside information, no committee seat, no say in banking policy. A ban says she's corrupt by default. That's not ethics, that's guilt by association.
I hear the argument that even the appearance of conflict matters, and there's something to that. But the better answer is disclosure and recusal, not stripping away financial autonomy. A blanket ban fails the utilitarian test: it burdens thousands of honest officials to catch a handful of bad actors, and bad actors will just hide stock in trusts or crypto. That's just shifting the problem.
And deontologically, it treats people as means, not ends. We don't ban all driving because some people speed. We enforce the laws and punish the violators. Is it right to punish everyone for what a few might do? I don't think so. The real fix is stronger enforcement, not overreach.