One of the problems with seasteading is getting reasonably inexpensive, reliable, high speed internet far from shore. This research team has demonstrated that using Free Space Optical (FSO) technology, they can maintain a 1-2 Gbps connection over 25 kilometers, even in choppy seas and fog.
"The team achieved more than 14 hours of link-up time, including during 4- to 6-foot high seas; 1-2 Gbit of error-free data transport at ranges greater than 25 km; voice communications at greater than 35 km; chat messaging out to 45 km, the maximum available line of sight; and repeatable, semiautomatic reacquisitions over the entire line-of-sight range."
https://www.laserfocusworld.com/optics/article/16569157/johns-hopkins-team-demonstrates-highbandwidth-freespace-optical-communications-at-sea
"The team achieved more than 14 hours of link-up time, including during 4- to 6-foot high seas; 1-2 Gbit of error-free data transport at ranges greater than 25 km; voice communications at greater than 35 km; chat messaging out to 45 km, the maximum available line of sight; and repeatable, semiautomatic reacquisitions over the entire line-of-sight range."
https://www.laserfocusworld.com/optics/article/16569157/johns-hopkins-team-demonstrates-highbandwidth-freespace-optical-communications-at-sea