The libertarian philosophy is to voluntary transact, associate,
and exchange with people. It does not mean everyone is required to
do so with everyone else.

Given they are hi-tech focused it makes sense where they are
situated. However, they are registering their Seasteading ships
with either the Bahamas, or the Marshall Islands, not the US. They
also DO have a few Latin-American companies signed up.

Finally I’m sure they will have in fact, a small amount of low
or lower skilled employees onboard to handle non-high tech duties.
Not just maintenance, janitorial, but the list above shows
entertainment, recreation, sports, music, food, beverage, etc.