rob: And I think saying such a thing costs you your Chelek in Olam Haba. The only potential cases where we can say Chazal were wrong are medicine and science (if you hold that Chazal could be wrong on those; but I think the vast majority holds that that’s a valid Shittah).
Let me be clear. I don’t know if the Tur Shimon story happened. I don’t even think that I care. In a sense, it’s irrelevant. Whether the city existed and that’s what happened or not doesn’t matter. What matters is that Chazal say it happened and give a reason. That reason is part of Torah Sheba’al Peh. It could be that Chazal made up a city to teach us this lesson. But that doesn’t matter. The lesson is still part of Torah Sheba’al Peh. You can deny the story ever happened. But you cannot dismiss the lesson of it. Doing that falls under Mach’chish Magideha.