I doubt that this is going to happen anytime soon--as it would face considerable Constitutional challenges.
The U.S. Constitution, Article I, Section 2, Clause 3, states:
And the 14th Amendment, Section 2, reaffirms:
This includes citizens and non-citizens alike—legal permanent residents, visa holders, and undocumented immigrants.
The Supreme Court has never upheld an interpretation that allows the federal government to exclude non-citizens from the decennial census for purposes of apportionment. In fact, legal precedent affirms that:
All persons residing in the U.S. must be counted, regardless of citizenship status.
The U.S. Constitution mandates counting the “whole number of persons” in each state for apportionment.
This does not permit restricting the census count to only U.S. citizens.
Any attempt to exclude non-citizens would almost certainly face significant constitutional challenges and is inconsistent with existing legal interpretation.