"Old music is usually better music" is survivorship bias. I'm not saying you're wrong but this is something we should have in mind when debating music in general.

I’m going to somewhat disagree, at least in principle. In the past three years I have heard so much good new music, music made in the last five to ten years, or even music made the year I heard it, that I think it’s out there. It’s just much more difficult to latch onto. There’s so much new stuff that’s just palatable, there’s a lot more access to music making gear and equipment that just about anyone can release an album now.

Popular music is mostly dictated by the law of supply and demand, if an artist is easily marketable then a record label is going to invest. Most streaming platforms are designed to spotlight up and coming artists (most marketable artists), or those artists who already have massive fanbases (market stalwarts). This wasn’t any different 50 years ago, but 50 years ago there was a higher standard for what music got to be released. There was also a much higher bar to entry for recording studio-quality music.

Old music is usually better music

There is so much music being created right now, that there is simultaneously more good music and bad music than in the older days.

Radio hasn't been a metric since like 2010. The indie scene is where it is at and it has never been bigger. Plenty of bands making classic rock music if you are into that.