[yurishimo]

Because they require a lot of maintenance for people who aren't even sure they enjoy cooking for 1 minute more than absolutely necessary. I understand that carbon steel is a lot less maintenance than cast iron, but it does require maintenance.

By comparison, you can soak a stainless steel pan in water for weeks with basically zero negative consequences.

Also, if you live in a culture that frequently cooks acidic dishes, then you're working against yourself by dissolving the seasoning constantly. I also understand that it's fine in moderation.