Sure, but (ignoring the Constitutional decennial mandate, which also requires Census subjects to be defined 3 years before the actual counting [0]) what's a cost-effective alternative? The budget for the 2020 Census was $7+ billion [1].
And while the ACS annual surveys are considered accurate, what would be the right period for changing Congressional seat counts? It obviously can't be annual (since House terms are every 2 years).
[0] https://www.census.gov/programs-surveys/decennial-census/abo...
[1] https://www.census.gov/about/budget.html
