I think another part of it was the effort required to try out new titles; I got very attached to the Dizzy series because I had to save up my pocket money and actually go to the computer shop to buy the tape. And that shop certainly didn't stock 15,000 different games :) Kind of the same way music discovery used to be, only with demo tapes instead of the radio. (I still wonder if the demoscene could come back somehow.)

With the barrier to entry being that of downloading a Minecraft mod or free app, it's harder to get anywhere near as attached, in my opinion; but I don't have kids, so I wonder what they do spend their hard-earned pocket money on instead?

For a similar nostalgia trip I recommend reading Only You Can Save Mankind by Terry Pratchett.