It's not a panacea. It's a part of the very complicated system that is providing and paying for healthcare. How important are insurance premiums relative to other factors? It depends. But there are costs to having uncapped settlements, and lack of tort reform.

Also, insurance premiums effect practices of different sizes differently. I personally think you can attribute the shift away from smaller private practice groups towards larger groups and hospitals are for other reasons. Insurance premiums are somewhat to blame, but I think the bigger driver is that many of the government mandates are too expensive (n.b. this doesn't mean it shouldn't be done) to take on for most smaller private practice groups.

I'm not sure how to respond to your comment about tort form if it get's us to an NHS like system, because I disagree that's the best way forward. But that's a topic for another day.