I understand and agree with your sentiment, but just don't buy the uni-tasker type lego. They make plenty of sets where most if not all of the parts are general and can be used for undirected play.
And for lego fanatics you can buy specified unit-sizes in specified colours, so there is that.
We got a lot of themed play stuff, fences, trees, animals. I do recognize how much kids love themed play too.
Back in the 60s/70s I had the trainset, which included a "one noise forward two noise stop three noise backward" controller. There were two or more generations of the train motor: the one with rubber anti-slip on the wheels and the one without. depending on how much you enjoy crashes, either were useful...