The empirical argument actually states that memory access is O(n^1/2)
https://www.ilikebigbits.com/2014_04_21_myth_of_ram_1/3_fit.... "The blue line is O(√N)."
This has been rehashed many times before, and the best blog post on this topic is here: https://www.ilikebigbits.com/2014_04_21_myth_of_ram_1.html