The plan was for it to stay closed and have the US sell oil.

The US is now exporting more oil than it has in a decade.

Why can none of these supposedly smart people see this plan?

There's no 4d chess plan here.

Trump thought it would go exactly as Venezuela and has no idea how to fix it. They tried to kill enough of Iran's leadership to get to somebody that would be subservient but it turns out nobody is left alive in Iran that is.