You are asked these things no matter you level in FAANG interviews. You need high enough intelligence to understand how to solve these problems if you are shown

You are asked these things no matter you level in FAANG interviews. You need high enough intelligence to understand how to solve these problems if you are shown a solution, but I do not think you need much more intelligence than that to do well in a FAANG interview. It's more about how fluent you are given that you have already done some prep.