No, you're exactly right. The author defines "weakness" versus "strongness" as whether you can do something like "int + array" and get a result other than a type error. ECMAScript is very "weak". Haskell is ridiculously "strong" by this definition, since you get a type error for computing "(1 :: Int16) + (1 :: Int32)". As far as stricter languages go, there is perhaps only Ada.
There are two kinds of language comparisons I've seen:
1. Language comparisons posted by dabblers, which you could scrape together by reading Wikipedia. You see a lot of poor logic and unsatisfying definitions, because if the logic were sound and the definitions useful, a dabbler would never have enough expertise to write the post.
2. Language comparisons by experts, which restrict the discussion to history, the underlying logic of type theory, or empirical observations about a small set of languages.