Don't have public / private split but pretty sure 90K for 3YOE isn't "average" like you suggest. If you look at this calculator based on MOM stats then you'll see that for age group of 25-29 $7-8K monthly is top 11%..

s://.straitstimes.com/multimedia/graphics/2024/07/salary-guide-2024/index.html?utm_campaign=STPicks

You may argue that this included non degree holders, but about 36% of resident population above 25yo are degree holders. Given this, I still think 90K annual is above average, whether private or public.