It’s all context. Some cultures are loud, some are quiet; some people are loud, some are quiet; some places are supposed to be loud, and so on.

The people being quiet in an normally-loud place create no problems. The people being loud in a normally-quiet place are causing problems for others by violating the quiet.

Loud people also tend to be oblivious to this and then get defensive when it’s pointed out. Not always - I’ve known some naturally-loud people who had figured out that being shushed meant they were in the wrong.