Inside a Computer System: Well, yes, this is how virtuality works; the computers simulate the entire environment in full fidelity – which, I hasten to add, means even more when you have to come up with appropriate outputs for all possible sensory ranges of your polyspecific clientele – and then your sensory-link implants substitute this input at the sensory center of your brain. Old technology – safe, reliable, boring, been around for millennia.
Does not, I repeat, not move your consciousness anywhere – it remains in the gooey paste inside your skull, or whatever else you happen to think with. That’s what differentiates virtuality from uploading (which in any case requires quantum processors, which is by no means all of them), or voodoo – but see below.
Digisapiences, and other native digital sapients, don’t actually dwell in virtual spaces inside computers, I hasten to add. They’re programs; their senses aren’t like ours, and don’t need concepts like “space” and “shape” and even occasionally “time” to work. They inhabit the processors raw.
Finally, while it’s not technically within the meaning of this trope, most people are at least partially within computer systems at all times, mostly because – once you get into the habit – most people’s minds are too big to fit in their brains any more. Most people in advanced societies live their lives surrounded by an exoself, a sort of computational fog of data and software agents and thought-threads and daemons and suchlike doing auxiliary cognitive tasks, and since there’s only so much computational power you can cart around personally, a lot of them offload the less important parts of their current thinking to processors out there, somewhere, in the cloud. (A bit difficult, of course, when abroad – hence, the existence of, among other solutions, thinking-brain dogs.)