No one considers A*s or 9s bad because they are literally the highest you can possibly get.
Having said that, I'm someone who would have a meltdown if I got anything less than an A and would be disappointed if I did get an A (barring AS levels where A is the highest grade). Why? Not because I want attention (I actually do my best to avoid telling people my grades), but because I have high standards for myself and thus am used to getting top grades.
This isn't written with the intention of sounding arrogant, but is the truth for those who always get A*s.