No. It is in the 28 tree.

That sounds interesting:

https://arxiv.org/abs/2004.02504

"Though still a work in progress, our implementation is able to bootstrap a functional Emacs and compile all lexically scoped Elisp files, including the whole GNU Emacs Lisp Package Archive (ELPA). Native-compiled Elisp shows an increase of performance ranging from 2.3x up to 42x with respect to the equivalent byte-code, measured over a set of small benchmarks. "

Yup. This is currently developed in a feature branch.

"Based off" would be more correct.