Many, if not most, of these occurrences can be made safe. It's very rare that I need `as`, and even more rare that I can't actually check the relevant properties at runtime to ensure the code path is valid.
It's on you to ensure that you don't misuse `as`. If I could choose between current TS, and a "safer" one that's less expressive in complex cases, I'd choose the current one any day of the week.