No, when the system you're interfacing to is itself a console, it is not "skeuomorphism" to present the user with a console interface.

Skeuomorphism is an aesthetic strategy for making software appear familiar or comfortable (or "retro" and stylish) by evoking parallel hardware/real-world solutions to the same problem. A console, on the other hand, is a way of interacting with software using typed commands.

An overlay for HN that presented it as a Renegade BBS instead of a series of web pages and web forms might be skeuomorphic, because that Renegade BBS interface would exist for aesthetic reasons only. But aesthetics aren't the reason you make a web SSH prompt look like a console.