As much as it fun to rag on supposedly out of touch economists, this "cheapflation" phenomenon is very documented and accepted among mainstream economists. Like many others in the public sector, government economists have been calling for more suitable and timely measures of inflation for decades, only to have their requests for more funding and support denied as the public service falls apart.

Price discounts and cheapflation during the post-pandemic inflation surge - ScienceDirect - https://www.sciencedirect.com/science/article/pii/S0304393224000977