Should a coastal home on sandy soil have an encapsulated crawlspace? Or is open air best?

Home built in ’76. Bottom floor added at some point which created a small/tight crawlspace. It is cinderblock around but it is pho and not actual structural support. There are vents and a door. when the home was purchased, the beams were covered by plywood and insulation bc ac vents were present. AC, insulation and plywood all removed due to a hurricane and getting wet. (Now have mini splits on bottom floor for HVAC)

Moving forward, our pest company recently advised encapsulating or doing a partial. They were concerned that some of the beams are showing rot.

It’s not ideal bc of location, sandy soil etc. Ground water is present if excessive rain. Thoughts? Most homes are open air underneath here with pilings or on a slab. We have pilings that a bottom floor was enclosed around. (Coastal VA)