My personal thought, with nothing to prove I'm right is ... he was setting himself up for ex-president, and that habitat for humanity scam.
Yes, Carter signed the CRA into law. As for the rest, I think it's more a case of the left's relentless legislative assault. They're willing to put *something* in the law books, even if it seems innocuous or non-threatening.... the sort of "throwaway" bills that generate no heavy opposition.
And then they come back a dozen years later and amend it, usually by attaching the amendment to some unrelated bill. They know how to game the system, it's as simple as that.