we are all one consciousness experiencing itself subjectively, brilliant... lol wow this blew my mind actually and I will not pridefully try to dismiss this but simply accept it, thanks.
You can argue with the logic if you want, the quote is from a dead man so you wouldn't get a great rebuttle from me. I just replaced a non-forum appropriate word in the quote with a topic related one. The guy was Bill Hicks btw he was really funny imo.
Immersion would be perceiving the game as reality, now the question is why would one want to do that? My opinion would be, to escape this reality which would be a drug inducing effect on the mind I explained in earlier text, similiarly to why people do drugs, to escape reality.

I've done a lot of highly controlled (but legally approved at the time of use) drugs and I never did them to escape reality,
In a non-judgemental way trying to immerse into a game to the point it is reality would be more of akin to a disorder like multiple personalities or dimensia than drug use.
On another note..if you're having trouble with reality sometimes you really have to search it out but there is someone around that will try to help you if you need it. If you don't believe me I'd be happy to prove you wrong.
Somewhat on topic actually read an interesting article about scientists discussing how they were attempting to creating artificle intelligence, one of their biggest problems was even if they made it how could they get it to do anything other than sit around and play video games all day?
Basically I think if a sentient creature can sustain it's own life it'll just feel like doing whatever gives it the most satisfaction with the least amount of effort. I think it would be a bit of a stretch to call myself a sentient but I know I do whatever gives the most satisfaction with the least amount of effort quite often.