I don't completely agree.
Yes, SQL is a great success but no, the declarativeness was not enough and we end up generating SQL through ORMs, query builders, templating, etc
I agree that there should have been more innovation on thosd aspects of query languages!
It's a little bit tricky because there aren't much low hanging fruits for academics to write good papers about, so this innovation is up to programmers who want to improve their quality of life when dealing with databases.
