I really don’t have any idea what you’re talking about, and think you may just have… visited loud places? Yes, they exist.
Like yes, a place that has loud music running is… loud? No surprise there? Why do go there, lol?
Yes, if you’re in a bar in Berlin Mitte on a saturday night that’s just packed with drunk people… that is loud. I don’t see how that’s specific to Germany. Ever been to any pub in the UK? I usually can’t understand my neighbor there and that’s on a regular wednesday evening.
The bars I visit in Berlin don’t play music at all, and I wouldn’t know any restaurant that plays loud music. And I’m really terribly sensitive to noise.
Also Germans are known for a lot of things, but not necessarily for being loud? On the contrary, most people consider it rude. I’ve been to most of Europe and also abroad, and Germans generally are really more on the quiet part of the spectrum. Spanish expats in Berlin, e.g., literally the first thing they are being told is to stop shouting.