Sure, and TypeScript is great, but I was talking about HTML rather than HTML plus all the layers people have added on top. I'm also not totally convinced Types

Sure, and TypeScript is great, but I was talking about HTML rather than HTML plus all the layers people have added on top. I'm also not totally convinced Typescript actually answers the point in question. It's a superset of JS in the end, and a part of why Java/C# type languages are popular in the enterprise is the list of things you can't do. Adding types can help, but it's not something that TS can enforce.