“It wasn’t repealed by the law...it can’t be.”
Read it again. It can be and was; partially in 1872 and fully in 1898.
The clause is still in place. A law cannot repeal a portion of the Constitution - which an Amendment is - it can only provide definition.
In this case, the cited law limited the definition of those to whom the Amendment applied. That is important, but it is not a ‘repealing of the Amendment’. That clause is still there, and it could be re-engaged, but only through new law, and likely not ex post facto.