Another excellent question! So there are a few different approaches. The floating shell and kevlar heads certainly does make for a drier sound. Depending on the thickness of the kevar and the coating, etc, you can significantly change the tone of the drum. (example: Remo Black Max is thicker and has a heavier coating resulting in a much darker tone than a Remo White Max.) You can also change the sound by using metal snare wires (aviator cables) compared to artificial gut and changing the tension of those snares at the snare strainer.
Shell / hardware design simply allowed for higher tensions. Back in the 80's, we double rimmed everything (see image above) and cranked the top head until the drum screamed. Once kevlar became a "thing" again around 1990ish, we started collapsing shells like crazy. The impact of the head / free floating design is what gives the drums now that less resonant, drier sound that you are referring to. Mylar heads and lower tensions give a more open, fat sound. Also, you can put a kevlar or hybrid head on the snare side of the drum and make it sound even more like you're playing on a table top.
I think the tuning is getting better, and honestly, I think having them cranked too far down not only chokes the sound but also is harder to keep in check wise from player to player (I am unsure about judging.) Some drums are easy to tune (Pearl) and we've gone away from over tuning as much. I compare it to 1980's hairstyles. We used to "Tease it to Jesus" and now it's a bit more toned down. Higher tensions are also a lot harder on the hands for young drummers IMHO