There’s actually less specialized parts these days, that’s what put Lego in trouble in the 90s, I think what GP commenter was referring to is a ton of the studs and cylinders and 1x1 diagonal parts that Lego includes, that are “fluff”. These parts are extremely cheap to produce, so you may have data that looks like price per part is flat, but in reality that’s because more of your sets are now from cheaper detailing parts.
having collected through the 90's, I can attest that there are a lot less specialty parts now, but in recent sets that number appears to be growing again. almost every fairly large set I've purchased in the last 2 years have had 10-12 new-to-me parts in it, and the other sets continue to include those same parts as well.
mostly, they've been pieces to make some change for SNOT, but there seem to be so many of them now that it feels like we're going back to that 90's mentality.
some of those sets:
* batman shadow box (with my first ever missing piece!)
* dune ornithopter (great build)
* loop rollercoaster (not counting those loop tracks)
* orient express (my least favorite build in the last few years)
