On topic, I played for a bit way back when it was still in a rough beta, and many of the people who convinced me to try got really involved for a time. It is so simple that it is addicting, particularly if you are the type who loves to create things. Minecraft is the modern day "legos".
Don't do it. Seriously. I regret the day Minecraft ever entered my household. My sons are obsessed with it beyond school, sports, girls, food, bathing. It might be like 1B to oxygen and underpants. Their friends are all the same way. It's a ---smurfing--- pox on my household. Every time I make them stop playing to do something they need to do (e.g. eat dinner, math homework, shower) they immediately start lashing out at each other from the separation anxiety. It takes them well over an hour to transition out of Minecraft and back into the real world but only about 10 seconds to sink back in. Grades have dropped and hygiene has suffered. On a weekend if I don't go looking for them I would never know they are in the house other than the occasional Minecraft sounds from upstairs.
If they didn't have minecraft, they would find something else. It is just life in this millennium, get used to it.
I could also say that there is nothing new here.. you give a kid something he enjoys immensely and leave him to do it completely unregulated and chances are he will indulge at an unhealthy level. This would be why parenting is kind of important.. You can tell a kid about moderation, but until you enforce it you only be enabling it.
Trust me, there are worse things a kid can get hooked on than a video game.
As for the technical capability of people, I have found over the years that a person's capacity to learn is directly proportionate to his desire to understand it. Some people just have no desire, deep down, to truly understand how some things work, and hence won't take even the most minimal effort to truly grasp what is behind the devices they use. Without a desire to understand a piece of technology, using it becomes a question of how well they can memorize steps in a process. Those of us who have a strong desire to understand things turn out to be the most adaptable and have the highest ability to sit down with something we don't know and figure it out.
But when technology really exploded a few decades back, the excuse was always that they didn't grow up with it so they didn't understand it. I have worked with a surprising number of 60 year olds who after a few hours of training will grasp and understand a piece of software enough to figure the rest out on their own and never need basic support again. And I have worked with a surprising number of 25-35 year olds who even after three times the training fail to have more than a rudimentary capability to do what they have been trained to do in the same software. It isn't familiarity or even intelligence that is the determining factor, it is whether they have the desire (and capability) to understand it that makes the difference. Everyone who uses technology wants to know how to use it, but wanting to understand it is something entirely different.
I think this applies to people in technical jobs as well. I always look at it as a technical support situation.. there are your "tier 1" technical support people who might be enthusiastic about technology but not truly have a desire or capacity to understand it. These people are perfectly capable of listening to a problem or request and choosing from a set of predefined answers that may or may not work. But as soon as the problem is beyond their method of troubleshooting, they have to defer to the next tier of technical support. It is not uncommon for a company to hire someone who is enthusiastic or because they interview well, and again, the stigma is that if you are younger and grew up with the technology and are enthusiastic about it, you must understand it too. I think most of us here would probably end up as tier 3 or 4 tech support because we all share this desire to really dig into the "how and why" and come up with solutions that are outside of the box. All the enthusiasm in the world for playing arcade games is not going to amount to anything when it comes down to building one yourself if you don't have some kind of desire to understand what is really going on "under the hood".