So the Supreme Court ruled few weeks ago that the final deadline for 2020 consensus is october 31st. So what this means is that this saturday they will terminate active field work for counting population and by december 31st they will announce the official population of the United States. Population is counted every 10 years and it has tremendous impact ranging from federal funding to number of electoral votes in each state, number of seats at the United States House of Representatives and so on. So the rule of thumb here is that the more population each state has, the more electoral votes/seats it gets. President Trump has been fighting hard to exclude illegal aliens from the population because they heavily inflate the numbers and give states like California huge advantage(not to mention they are 100% of the time voting for democrats) By building the wall, President Trump severely cut California's supply of illegals and now he only needs to make sure illegals will be excluded from the 2020 consensus. In fact California has 55 electoral votes, way more than any other state. President Trump also took this issue to Supreme Court and if he gets a win there before december 31st deadline, it'll mean California and other states filled with illegals lose huge amount of seats and electoral votes which will immediately affect 2022 midterm elections and beyond.

https://www.whitehouse.gov/presidential-actions/memorandum-excluding-illegal-aliens-apportionment-base-following-2020-census/

https://www.nytimes.com/2020/10/13/us/supreme-court-census.html

PS: I was trying to quote NYT article here and even tried to remove a lot of stuff from it but still it kept saying my text was too long.