Sure, you could make a fix for this specific case, but the problem mentioned in the blog post is not even close to the only problem of non-ASCII characters. In theory, yes, we could make a language and a full suite of tooling that would play nice with non-ASCII characters. But it's not like the whole non English speaking world is waiting for this to happen. People code in English even in teams where everyone speaks Finnish. Nobody even questions it, because it's so obvious that all code should be in English and ASCII. Everyone has shot their foot, putting in non-ASCII characters in the source code at some point of their career, if they have ever dared to try. That's how the reality is, and at the same time I hear people saying that the existence of those Finnish programmers means we have to have Unicode in source code.
>That's not what I said at all. I don't see how you came to this conclusion.
I didn't say you said it. I said that's how it (probably accidentally) comes across when you talk about something so carelessly. Non English speakers care about compatibility and security and take those seriously, therefore we pretty much always write code in English and ASCII.