What I'm talking about is running an IDE as a server and being able to connect to the same session e.g. from different machines which do not run a copy of IDE.
Imagine running all the real-time code analysis tools on a beefy corporate server while the editor component runs on your laptop. Imagine attaching to someone else's session to collectively debug a problem or review code, right in the IDE. Imagine your laptop losing connectivity / running out of power, being reconnected and recharged, and connecting right back to the IDE that never lost its state. Imagine running the IDE, or parts of it, in preconfigured and isolated containers / VMs.