My own skepticism isn't so much stemming from any belief that the current legal systems are particularly great as it is from the learned reflex to be wary of anyone rewriting a system from scratch.

The legal system is complex and messy sometimes because moneyed interests have been keeping a thumb on the scales and sometimes because the world is complex and millions of people have spent hundreds of years patching bugs and extending the code to handle all the weird corner cases.

Smart contracts are a neat idea, but it is also kind of like the guy who wants to rewrite the production system in a weekend.