You're moving the goalposts.

GP was concerned about MS nefariously introducing vendor lock-in by implementing a bunch of their own proprietary features. I've demonstrated pretty clearly that

1. It's not MS's implementation - it's an implementation of an ES proposal.

2. For the one example you could find, MS didn't even want to do it - it was requested by Google for Angular and done as essentially a compromise. If you browse the TS repository, you can find issue after issue of the TS team refusing to add features that aren't part of the ES standard.

I think this shows fairly definitively that this is not a case of MS trying to lock you in to their product.