I like efforts like this that try to use different wording to explain the same concepts. That said, this document still uses words I would not consider to be "simple English".

There are many such cases in the document, but let's take for example "inference". There is a definition of what "type inference" is in the first paragraph of the section. But the reader must still then learn this phrase at the same time as learning the programming language. Maybe a simpler English statement would be "Automatic types", using the word automatic, which is more wide spread and is adopted in many languages. The meaning is not as precise but the document can then further explain what it is.

I am not a native English speaker but have become so used to using it that it is sometimes difficult to know which terms cause issues to programming language learners. Perhaps HN is the wrong place to ask this but I would be very interested in knowing which terms other non-native speakers have problems with.