Once, I played a virtual reality game where robots attack you and you shoot them. This was a very fun and compelling experience despite being rather basic. In fact, it was too compelling -- the experience was so intense that I had to stop playing, as I thought that if things got significantly more intense I might have a heart attack and die!
This experience got me thinking something along the lines of: "Huh, virtual reality technology is rather primitive, but already an experience can be that intense? What will it look like once virtual reality environments have much more time, thought, and technical advancement put into them?" The prospect seemed pretty worrisome to me for the future of the technology and how it might impact society and civilization. (Of course, fears of negative ramifications of virtual reality are by no means new, but having a direct experience of it made me put more thought into the matter.)
However, I brought this up in an online conversation recently, and another user, ohAitch, made a very interesting point in reply -- many of our friends spend huge amounts of time on textual fiction, such that virtual reality might well not be a big important step!
This made me realize something -- for many people, these dangerous virtual worlds are already here. For some people it is the virtual socialization of Facebook or Twitter. For others, it might be non-VR games like World of Warcraft or Counter-Strike -- there have been multiple cases of people dying at their seats after playing games for hours on end in Internet cafés. For others, it can indeed be textual fiction as ohAitch said -- webfiction, online fandoms, and the like can be very consuming.
Yes, virtual reality could certainly be immersive and dangerous in a way that some of the earlier things haven't been, could make it easier to fall down a slippery slope, and so on. I think there's a real threat there -- but there are also some threats that are already here and which it might be prudent to pay attention to. The risks of dangerous lotus-eating are real and present today, and if we only worry about what future things might bring we may miss the dangers that are already around us.
 I personally know people whose lives have in my view been substantially worsened by Twitter politics in particular.
I thought that if things got significantly more intense I might have a heart attack and die!
I was initially skeptical that this was a risk worth considering. I've heard anecdotes of people dying of excitement, but seemed like a "shark attack" sort of risk that's more discussed than experienced. However, some Googling revealed "Cardiovascular Events during World Cup Soccer", which finds that cardiac incidents were 2.66x higher on days the German team competed during the 2006 soccer world cup. FIFA's website says an average of ~21.9 million people watched each match. This website says Germany had a population of 81,472,235 in 2006.
If we attribute 100% of the 2.66x increase to 21.9 million soccer fans being more excited on those days (as opposed to getting less sleep, drinking more alcohol, etc.), then we get (CV_risk_x * 21.9 + 59.57) / 81.47 = 2.66, so CV_risk_x = 7.18x higher risk due to extreme excitement. If we arbitrarily attribute 33% of the increase to excitement, we get (CV_risk_x * 21.9 + 59.57) / 81.47 = 1.548, and CV_risk_x = 3.04x.
That's higher than I expected, but still not too bad, especially if your current risk is low. I think virtual reality in particular is less of a risk than many other high-excitement activities because it involves more exertion than, say, normal video games or reading. I expect the increased exertion on net more than balances out any excitement risks.
Interesting stuff, thanks for the info! Subjectively it felt like "this is one of the most intense experiences of my life, my heart is pounding" etc. etc.
On the bright side, I expect this to be a slower-moving trend than the main AI risk, and also easier to combat, and also less dangerous. But I might be wrong. (See: "New and powerful forms of addiction" in this list.)
It's worth separating harms of wasted time vs degraded experience in a given lifetime. It's also worth comparing against the very similar worries of previous generations. How much time is spent reading fiction, listening to rock and/or roll music, watching television, playing D&D, etc. seems to be a perennial concern, only with changing specifics.
Yes -- I think that all of the examples you mentioned are things that can become a dangerous virtual world for at least some people.
Once, I played a virtual reality game where robots attack you and you shoot them.
Asking because I want to know, and I'm also curious if 'better gaming'/graphics/whatever can sour people on older (presumably) lower grade stuff.
A political newspaper that is optimsed to maxime a sense of belonging to a certain receivement of a world I thought was going to be one of the dangers. I guess for that differs in that the consumer doesn't know it is fiction. But still being correct is boring and scracthing those belonging itches might be a replacement to the "inferior" reality.