I think each generation is just growing up with shorter and shorter attention spans when it comes to entertainment. Got nothing to prove that though - just a casual observation that could be totally inaccurate.
I don't know, looking at many what many of the "older" people around me do, I can see that they prefer "simple" entertainment, the kind where you don't have to put much effort into it as much as the current younger generations. The difference for computer games is that they are reaching a wider and wider market, and thus has to appeal to more people.
During the 80's, most people who had an interest in computer games were also roughly in the same category of people as those who enjoyed complex wargames like ASL or roleplaying games (there were also the small time killers, like alley cat and other very simple games where the goal was simply to get a high score, but those served roughly the same purpose as free cell does). Console games held a "lower" standard, as far as the amount of effort & time you had to put into them went. During the early-mid 90's we started to see home computers really reaching a wider audience, it was no longer just a thing for the "geeks" and the people who had to work with computers, and thus games were becoming simpler. It is a matter of evolution really, games are evolving to become more accessible and easy to pick up and play for the common person, not just the person who is ready to spend hours upon hours learning how to play the game in question.
The interesting thing is that we don't really see a drop in popularity when it comes to other more effort consuming (from an intellectual point of view) things. Books like War & peace, crime & punishment, the people of Hemsö and other classics still appeal to the same basic type of people in the younger generations, and that one has not percentually shrunk.
And look at TV shows. Most shows from the 70's and 80's were just as "dumb" as those of today, just as simple and requiring just as little effort.
I don't really believe in the view that todays younger generations are having such a short attention span as some people might thing. It is just a matter of perception, when some of you were in highschool, you probably spent time with the "geeks", that was the reality that you experienced, but as an outside observer, the geeks would just have made up a small portion of the whole, probably a hardly noticeable portion. Of course, the term geek has become a lot wider, there are more types of geeks, and there seem to be more geeks in general, but the percentage of people who are willing to take the time & effort to really learn those more complex games are probably roughly the same, and the amount of people who never had the privilege to have the opportunity to develop a long attention span are also probably roughly the same.
And we are seeing a bit of a counter reaction to all of these "dumbed down" games. Small scale development of more complex games is going on. Rogue likes are making a return, and games like Minecraft & Dwarf fortress (two games that you have to spend a lot of time with to really get anything out of) are becoming huge hits.
And there is actually a company that has made quite a lot of money during the last 10 years making very complex strategy games, the kind that you really have to put some effort into. Just look at Paradox entertainment and their Europa Universalis style of games (Victoria: An empire under the sun in particular). So there is still a large enough market for complex games to warrant creating new ones.
F ($50 for roughly 15hrs of game play) they can go stick it. Though the game play was fun, it was not very dynamic and the price was too high for what it was.