Let me propose a thought experiment with three conditions.
First, you're in a simulation, and a really good one at that. Before you went in, the simulators extracted and stored all of your memories, and they went to great lengths to make sure that the simulation is completely faultless.
Second, you can leave any time you like. All you have to do to end the simulation, regain your memories, and return to reality is recite the opt-out passphrase: "I no longer consent to being in a simulation". Unfortunately, you don't know about the opt-out condition: that would kind of ruin the immersion.
Third, although you're never told directly about the opt-out condition, you do get told about indirectly, phrased as a kind of hypothetical thought experiment. Maybe someone poses it to you at a party, maybe you read it on twitter, maybe it's a blog post on some niche internet forum. You're guaranteed to hear about it at least once though, to give you a fair chance of leaving. But it's vague and indirect enough that you can dismiss it if you want, and probably forget about it in a week.
It's not enough to think the opt-out phrase, you have to actually say it or write it. So the question is, hypothetically, would you?
Let's imagine that you've spent your whole life from birth inside an MMORPG. Who is then "you", separate from the MMORPG world, who could leave it? All your dreams, hopes, desires, thoughts, intuitions, personality, and all of your sense of "self" is formed by your experience within the MMORPG. What does that leave to the "original" you? Just the structure of the neural network with which you've been born? That doesn't sound like anything essential to me. Certainly it is not something I can even be consciously aware of, how could I call it "me"? OP says "the simulators extracted and stored all of your memories", but it's an error to think that "memories" is just some data on a flash drive, if you actually remove the subtlest footprint of all your experience, then what remains?
There is a great koan which asks to "remember your original face". There are several ways to think about it, but it points to the seeming duality between the subject ("you") and the object ("the world"), that you imagine being submerged in, being an illusion, because in the end the subject is formed by the same world and is inseparable from it.
PS if you would keep your "simulated experience" though, as in "The Matrix", then the thought experiment becomes coherent, because the continuity of self is preserved, and we can really say that it is "you" that moved from one world to another, but in that case it is not clear whether I should be treating my "simulated past" differently from my "real past" -- they both have just been formative experiences that made me into who I am now.