system
Given the following post, respond as if you're commenting on Reddit:
human
[Cyberpunk 2077] How is maritime travel still possible?

It is stated in a shard (and I believe other places) that during the 4th corporate war, Arasaka, in their benevolent wisdom, flooded the world's oceans with self replicating mines. This has basically made maritime travel nearly impossible and made the necessity to build a wall around Coronado Bay. Why then do we see multiple ships in the game? These range from simple cargo ships to an Arasaka super carrier. Even if Arasaka had the ability to disengage their mines (which they don't, since the mines believe their updates are a virus and reject them), that still leaves out Cargo ships which we know have in fact brought cargo from places like the USSR.
gpt
There are ways to temporarily clear a path and get ships through, and there are also safe zones near coastal areas where more hardened defenses keep the replicating mines away.

Maritime travel is basically impossible, but it still can be done at great cost and effort. All this did was limit non-essential travel and increase the need for in-country manufacturing as most transport is done by air and therefore more expensive.