Repiping is something Daniel Island homes essentially never need, so if it has been suggested to you, it is worth asking why.
Your pipe is modern
The reasons homes get repiped — galvanised steel rusting closed, or polybutylene going brittle — belong to houses built decades before this island was developed. Copper and PEX in a home from the late nineties onward is not near the end of its life.
What low pressure usually means here
If the pressure has dropped, the likely causes are a failing pressure regulator, a partially closed valve, scale in the aerators from hard water, or an irrigation zone drawing at the same time. All much smaller than repiping, and worth ruling out first.
The service line
The line from the meter to your house is yours to maintain. Because the island is built on filled ground, the occasional problem here comes from settlement or from someone digging into a line during landscaping work rather than from age.
Replaced without trenching
If a service line does need replacing, boring a new one through underground leaves the lawn, drive and irrigation intact — which matters on properties where the landscaping is part of the value.