While I don't agree with your prejudices, I do believe you're on spot here by saying that choice is one of the major factors in games becoming ever friendlier.
Not only are there considerably more games today, being pushed out with considerably more marketing. We're living in the age of free to play, where the next free game is just a download away. To make any kind of money in F2P, the developers need to keep players playing, so that they'll eventually pay. Basically the same goes for selling DLC.
So I'd say the lack of difficulty is mostly caused by how games are monetised these days.
Not only are there considerably more games today, being pushed out with considerably more marketing. We're living in the age of free to play, where the next free game is just a download away. To make any kind of money in F2P, the developers need to keep players playing, so that they'll eventually pay. Basically the same goes for selling DLC.
So I'd say the lack of difficulty is mostly caused by how games are monetised these days.