Why capturing an enemy fleet may be a liability

Can the campaign reproduce Copenhagen by seizing the Russian fleet?

Perhaps, but money or territory is preferable because captured AI-designed ships are usually poor assets that must be refitted or scrapped.

The joke is that the real question is whether the Russian fleet is worth stealing. Captured ships would bring their existing design weaknesses into the victor's inventory and would then need refitting or scrapping. Building ships to domestic standards at overseas stations is preferable even when captured vessels can technically be refitted. In campaign terms, cash or territory therefore offers more strategic value than a collection of poorly matched AI-designed prizes.