Where is disagree is we need to sort out our shit, come up with a plan for staying in and a plan for moving out and vote on a strategy for each with, details , plans and answers. The whole thing is a complete fuck up by Cameron and is going to have very bad consequences either way as it is all about nothing and there are no plans, strategies or facts out there. Anyone who makes a big important decision with no plans for afterwards and based on the rankings of a few politicians on each side is a fool and everyone in the UK is asked (in and out) to be a fool
In a perfect world, you are clearly correct. This is not the way an intelligent person would go about deciding a major personal issue. However, it is what we have been dealt...and politicians who clearly favor one side. Coincidence? I think not!
In a perfect world, we would ensure that whichever way the vote went, Britain was completely prepared. Alas, we are not, and we are not! So, against that backdrop, it is the easy side of the argument to suggest change is bad, because it holds unknowable consequences...much like all of economics, which is just theory based on conjecture built on preconditions that never actually exist!
In this instance, with Britain having a fairly strong economy, strong trading relations with countries all over the world, and a history of being a stable friend and partner across the globe (OK...recent friend and global partner!), it is in a very good position to ride out the initial shock to the system...which will all be trade/stock market/political, rather than internal.
If we lived in that perfect world, we could do as you suggested and look again in a decade or so. But, then what? Same place, different time, just that the scaremongerers will be 10 years older!
Britain needs a few shocks to the system regardless of whether there is a Brexit or not. Today is as good of a day as any to get started fixing what ails us.