An unsolicited PR that adds new syntax and changes the bytecode layout would 100% not be welcomed. There are stages to redesigning languages and that is the last one. But instead of having a discussion about it (stage one), people like to pretend like the current implementation is God's gift to mankind and anyone who disagrees should DIY or shut up.
why? would be pretty welcomed as proof-of-concept to start the discussion.
Nobody has said it would be merged immidiatly.
At least could be used to run load tests.
You can always start with EEP if you wanna to discuss or propose new feature - https://www.erlang.org/eep
