I'm partly deaf, so that doesn't help. However, I suspect that Asus (or Google?) is very worried about headphones making somebody deaf. I have a nice little Radio Shack digital AM/FM radio, and the headphones are as loud as I want. Nexus often is not loud enough with volume at max.
Another thing is that countless video producers don't care a fig about the sound level in their videos -- they are disgracefully low.
Business opportunity: Little box, couple of AAs, limiter with gain. Limit threshold set to minimize hearing damage.
Here's wishing better for you.