Sure, that's what it comes down to. Languages with implicit type coercion do have a set of bugs not found in strongly typed languages though, but the additional safety of a strong language is -- like you say -- gained at the expense of writing casts. That does seem like a trade-off worth discussing in an article about programming language design.
C# allows you to do implicit casts when you do not lose information, e.g. int to long. I cannot remember the last time I had to cast to something where I would potentially lose information.
However, I don't think manual casting is a cost at all - it's more of a guide telling you something in the design is wrong, or a reminder to make a comment of why you do it. And for any long maintanence projects, you want to catch all the bugs you can as early as you can.
