Yes Lego has very much changed. Like you I remember when the Lego sets you bought could build not only the Fire Station but also anything else your imagination could lead you to. (My Mum still has the Lego I played with as a kid) OK that is probably still the case today but the vast majority of sets now have very specific bricks making it slightly more difficult. But that has also meant the growth of MOCs, some of which are very impressive.
Like the newer Speed Champions sets, the complexity increases all the time and the amount and type of innovative building techniques always amazes me. There's some building steps and parts on my Creator Ferrari and more recently Technic Land Rover that are really interesting to get to the desired result, of perhaps just a brick in a certain direction.
Lego in our house has changed from toys and being played with to kits that are bought to build and display. Hope your collection grows as much as mine ๐๐ผ