When or if, an immigrant becomes a USA citizen, they are no longer immigrants.
If, for any reason, legal immigrants refrain from seeking full citizenship, they must also refrain from voting, and certain other civic duties.
There are no “undocumented immigrants”.
There are only foreign citizens who are granted various degrees of legal temporary or long term welcome as guests, or legal immigrants pending full citizenship applications.
Any other foreign citizens are illegal aliens, and/or criminal invaders.
All adult citizens, OTOH, no matter whether they are naturally born or were formerly immigrants, should be required to vote. (IMHO)
And each ballot contest/question should include a “none of the above” option.
let me guess,... the Supeream Court will rule that undocumented voters “have a right to choose”, or some other such aliceinwonderland reasoning as they always do