I think it has good and bad sides, but looking at the specs/draft-proposal for the new functionality being drawn and the hoops the syntax has to make in order to preserve the "it's regular language" while incorporating long time needed functionality it seems like it's a bad choice - one of those things that in some years people will go, "why tf is this like this"

I understand a proper parser would (perhaps) be more complex, but could also be open sourced in a lower level lang such as C, and then used by everyone, there's also already the full test suites for testing the output - maybe even Google+MS+Moz could open a contest - "fastest, most readable and efficient parser in C (or rust, wtv) takes 10k home"