I owned lego castles and spaceships sets even 30+ years ago.
I owned lego castles and spaceships sets even 30+ years ago.
One specific example I can give is with the chassis for small cars. In the 90s they were fairly generic. They were obviously intended to make cars with but you could build any kind of car or boat or plane or spaceship using it as a base.
Now I'm buying Lego for my kid and the car chassis have integrated tyre pins and mudguards, so it's hard to put on e.g. monster truck wheels (won't fit) or build it into a boat/plane.
So while specialized pieces aren't new, they're so very single purpose now. Not every piece, but enough of them that it's problematic.
[0] https://www.lego.com/en-us/product/garage-center-60232
[1] https://www.lego.com/en-us/product/service-station-60257
[2] https://www.lego.com/en-us/product/pirate-ship-31109
[3] https://www.lego.com/en-us/product/monster-burger-truck-3110...
[4] https://www.lego.com/en-us/product/twin-rotor-helicopter-310...
Those 3-in-1 sets really impressed me though! We've got two of them and as you say they come with instructions for several different ways of using the same pieces, and they're generic enough that you can build mostly anything.
We're definitely picking up more of those as both me, my dad, and my kid all like to just free-form build things most of the time. The creator pieces are actually really great because of the slopes and curved pieces that complement your ideas and help put the finishing touches on things.
I freely admit by the time I stopped, Lego was well beyond blocks: fences, animals, plants, roofing elements, train elements, turntables, windows, car elements...
The weirdest and less reusable were hollow corners (for the V shaped windows) the oval feets. The rest was very generic.