> …hundreds to thousands of such rules and the vast majority of them are _not_ that important.

And you base that on…?

> How does not wanting houses to flood relate to setbacks, minimum square footage, lot size, etc. requirements?

Here, minimum lot sizes are based on public/private water/sewer. We’re on well water so we need room for the well. We’re on public sewer, however, so we don’t need room for a septic tank.

As mentioned in other comments, minimum lot size also relates to infrastructure requirements. Here, it’s not as simple as just widening the current road or building another road through the narrow parts of our peninsula.

Setbacks are also related to stormwater management. Tree protection requirements, again, stormwater management and erosion control.

> Literally no one is saying "get rid of every single development regulation".

But you think that there are only an “_extremely_ small” number of valid regulations. You and the other comment I replied to seemed dismissive of specific rules that are vital to the survival—not just value, but physical survival—of my neighborhood.