Of course, the compiler or an advanced IDE can know what your code means. If all your identifiers were random permutations of l and I: lIllI1lI, your IDE would not mind either, but the code would be horrific, don't you agree? The point of the OP is that overloaded operators (and functions) make it harder to reason about the code for a human that reads it. At least for some people. At the end, everything is "just" syntactic sugar, but it makes a significant difference.
Exactly. If you don't care that the code is unreadable and you can rely on every human viewing the code through an IDE with symbol resolution (and not say, online code review platforms) and remembering to use said symbol resolution to check every operator, then operator overloading is great!