Thank God. If only because this would open up people born here to having their citizenship retroactively revoked. The constitution is pretty clear. If you don't like it amend it. If anything we need to expand it to include anyone who gives birth in this country. If you're willing to deal with our horrible maternity care system and help keep up our declining population, you deserve a blue passport.
No, that's not how laws work
Applying laws retroactively is much less common than a "simple" rule change