No. It does nothing. The lawsuit tried to force states to assign voter districts based on citizens over the age of 18 and eligible to vote. The court ruled that state are not so required, though they may if they wish.
This is actually an issue that goes back to the slavery and the drafting of the Constitution. Slave states wanted Congressional seats assigned according to total population; thus their non-voting slave populations would boost the influence of these states in Congress.
Non-slave states argued for the “Three-fifths Compromise”, that used only three-fifths of the enslaved population in the allocation formula for seats in the House of Representatives. It prevented slave owners from controlling the House with seats allocated based on their slave populations, despite the enslaved individuals not being allowed to vote and petitions these Representatives!
The issue today is similar, but sort of the reverse. Cities with large non-citizen populations tend to get more seats in the state legislature, because they have larger populations. Even though non-naturalized immigrants cannot vote, they still have the right to petition the representatives serving their districts.
The lawsuit before the court sought to force states to allocate seats based only on US citizen population. This would have given more seats to communities with larger citizen populations, but not necessarily larger total populations. While this is a legal option for states to chose, it is a state legislature’s prerogative to decide if this method is best for their situations.
Forcing the states to allocate voting districts based only on citizen population could have a discriminatory effect on** legal non-citizens** in certain areas. Allowing states to choose their method, rather than requiring a single method, allows states better flexibility to avoid or mitigate this discrimination.