What will developers do?

Anything they are allowed to do. It is not their job to look out for us and the future.

As an example as to what they will do, one only needs to look at the flooding situation along the Mississippi River this year--in fact right now.

The taxpayers and the Corps of Engineers have build scores of levees along the River over the years to stop the natural flooding into a drainage plain that used to exist.

Those plains used to save down-river folks from flooding by relieving the pressure of the floods into vast overflow lands.
Those lands are now full of strip malls and new farms developed by developers. Today they are flooded out even with very high retaining walls.

Also, the height of the levees still doesn't relieve sufficient pressure to keep from flooding many down river!

These aren't mistakes made by ignorant humans! They either didn't care what might happen or if they did, wanted the money anyway!

It is just as Rushe Limberger says, the climate changes every 10,000 years or so for some cause, and I'm not living that long.