It's very close though. The proposal is well written and covers the cases where existing Typescript code would not parse correctly/work as intended under the proposal. Most of those cases are pre-1.0 Typescript features still in the language for backwards compatibility but generally frowned upon and that you probably already have strict warnings and linter errors preventing you from using today. The big exception is a lot of TS codebases heavily use `enum` and I've still not seen enough suggestions to tighten the linter warning against it. (But there are at least some of us suggesting avoiding TS `enum` today.)
It's very close though. The proposal is well written and covers the cases where existing Typescript code would not parse correctly/work as intended under the proposal. Most of those cases are pre-1.0 Typescript features still in the language for backwards compatibility but generally frowned upon and that you probably already have strict warnings and linter errors preventing you from using today. The big exception is a lot of TS codebases heavily use `enum` and I've still not seen enough suggestions to tighten the linter warning against it. (But there are at least some of us suggesting avoiding TS `enum` today.)