There's more good music around today than there ever has been. The main difference is that you're expected to look for it yourself and with new digital media that's perfectly possible. Just a few weeks ago I bought a great new album by Amon Tobin because it was recommended to me by a lady in a specialist music shop.
The rose-tinted spectacles are mostly just that. Sure, the charts today are generally much worse than a few decades ago (I'm in total agreement there) but time is a natural filter of detritus. How many number ones do you actually remember from the 1970s? Number twos? Number threes? There weren't that many worth remembering; it's just that we tend to remember only the better material of the date.
As for the lack of dynamic contrast - yes. Although this is changing and there are plenty of groups advocating change.
Do yourself a favour and stop looking at the charts. Look elsewhere. It's not exactly difficult - get yourself a Spotify subscription (I had one for two years) and explore. In fact, why not experiment? Go to a real record store (they do still exist) and talk to somebody knowledgeable
For any of our UK constituents, if you want exciting and innovative new music there's a fantastic shop in Totnes (Devon):
I went in there just over a month ago and the owner was quite happy to play music we were discussing over her (beautiful) sound system that was connected to her point of sale. Genuinely wonderful.
If you want the same, boring guitar music you've been listening to for thirty years you can go to HMV. If you want the same, boring pop music that's been flooding everything for decades, you can go to HMV. If you want something interesting and exciting then you're going to have to do a little less complaining and a little more exploring.