Earlier quoted context omitted.
This does crop up all the time. You should also mention though that Lego still make and sell a lot of universal building sets. In Lego stores there are walls of bricks where you can select any bits you want. Yes, there has been a big rise in themed and licensed sets, and yes, some of them have specialised building parts that you can only really use in the set. But that's just part of the trend over the last few decad…
Sure. I wasn't exactly criticising Lego, just pointing out that the appeal of the ad is inextricably linked to the ideal behind the product. Lego is a business, of course. Those ABS plastic blocks are practically indestructible, so they're not going to grow by selling replacements for universal blocks...
Not to put the knife in too hard, but megablocks and other competitors don't even function properly when they're new out of the packet.