Not all your errors, dynamically typed languages still require testing.
And I agree, I tend to prefer type systems like haskell that offer better compile time assurance than testing, but my point is there's a large contingent of programmers who don't, and who drive uptake of increasingly automated and abstracted dynamically typed languages (this isn't a prediction, but an observation of how things already are).
When compilers/runtimes become smart enough, you won't need a static type system, because the runtime one will catch all your errors.
Here's why I think it's wrong:
Catching errors is not something that I want done at runtime.