It might seem superficially unfair that extremely rich recording artists who are still able to make money (like Springsteen and Dylan) can get their old songs back and make even more money, but termination rights were probably added with less successful artists in mind who might not have such lasting popularity. They might need exclusive rights to their material to put food on the table (to exaggerate a bit) as they approach standard retirement age.
Regarding record companies, even though they take risks in signing and backing talent, I think 35 years of piggybacking on someone else's creativity is sufficient.
