Yeah, that’s where the ‘IT professional’ lost me.
(They might have a complicated setup with everything overly managed … but this is just a new vlan, unrelated to anything …)

Not to mention you might want to have one for test purposes anyway.

Also there are alternativnes, like mobile data via phone hotspot.

Or giving a kid to play some horror game on your gaming rig.

Or saying you don’t have wifi, wired net only, why didn’t they bring an ethernet dongle??