There was so much great music in the 70s it would be impossible to try and list it. It's ridiculous to try and say all music from a certain decade is bad. There is always good stuff from all genres in all decades, just as there is always crap. I know, it's as individual as any other artform, but unless you've heard every piece of music from every artist, how can you make such a judgement?
I know, I'm going to regret this post.
Here is a small taste of 70s music.