I think that's wrong. The skilled musicians were here in the 80s, and they're here now. It's not about their musical ability. It's about their artistic taste. Those are two very different things. I've talked to highly skilled musicians who have taken their knowledge, skill, and talent, and applied it to a style of music that they love, and isn't particularly popular. For example, I spoke with the principle violinist of a major symphony orchestra. He's in his early 30s. He could make a lot more money playing popular music for millions of people, but he chooses to play classical music. I spoke with Drake, a rapper who is college educated, and is incredibly literate when talking about his music and his art. But he has chosen to apply his knowledge and skills to a style of music you don't like. Still, he manages to attract millions of people to what he does.
Should an artist, no matter how skilled or knowledgeable, be forced to play music he or she doesn't like simply because you don't like it? This gets to the difference between art and commerce. Just because a certain music isn't commercial doesn't mean it's not art. You're holding people to your definitions of what music is based on your taste and experience. That's not their taste or experience. They should be allowed to follow their own path and create the music that resonates with them and their audience, regardless of what you think.
Same with what happened to rock. The music changed because the circumstances changed. It went in a number of different directions. Some of it became extremely popular, some didn't. But that doesn't mean anything. It's just not "rock music" anymore.