the Church-Turing thesis is the bedrock of computer science, without which it may not even be a science. It defines, scientifically and uniquely, what computing

the Church-Turing thesis is the bedrock of computer science, without which it may not even be a science. It defines, scientifically and uniquely, what computing actually is, thus separating computer science from the other sciences and turning it into its own field. You can't possibly argue that this is a small contribution.