"Lawsuits cost money for both sides."
Yes, they do. The mainstream public didn't seem to have an issue with that when the county sued the private property owners for customary use - which failed miserably and was more anti-property rights oriented than the topic of beach restoration.
"Would it not be more reasonable and cost efficient to restore the beach?"
Cost efficiency may be a valid way to look at the county's desire to acquire public beach via nourishment - as opposed to outright purchasing of the beach via eminent domain and the expenses associated it. But so called "critical erosion" is not a justification in itself for acquiring beach front for public use. And therein lies the root of this issue.
On the other hand, as I stated many moons ago on SoWal, the county should first focus on eminent domain efforts only on parcels where the public has relatively easy access to and obviously not the whole beach. Even if the beach is nourished years out, the ECL (private property boundary) would then be all the way to the dune line. This would still allow the public access to the beach even if some catastrophic hurricane wiped out all the sand north of the ECL. Otherwise, the public could still easily be locked out of the "nourished" beach after a direct hit.
"You lose nothing but gain everything."
There are almost 1200 parcels of private beach front property in Walton County in the possession of many thousands of owners. In case you missed my earlier post, well over 90% of these parcels refused to provide a construction easement for beach nourishment in 2015. The vast majority of beach front owners did not want it. And I'm just making an educated guess that it's still true today.
That's why they are trying to force beach nourishment upon private property owners with this new legislation, effectively not having to get permission (construction easements) from the owners. If beach front owners "lose nothing but gain everything" as you suggest, then there wouldn't be any resistance to beach nourishment as evidenced in 2015.
And I'll say it again, if the county simply waits for the next major hurricane, then maybe the beach front owners will whistle a different tune.