New construction extremely noise-prone or sensitive to sound

Hello everyone!
We have been living in our 145m2 new building since Easter.
The exterior walls are made of aerated concrete with brick facing. The interior walls are made of calcium silicate brick.

Yesterday there was a situation that surprised me a lot.

We have a dressing room on the upper floor. My wife hung clothes on metal hangers there.
At the same time, I was sitting on the toilet on the ground floor. I clearly heard her sliding the hangers over the metal rods.

In general, the entire new building feels extremely noisy! You can hear every little thing. Even from the bathrooms...

Can you tell me something about this?

Did you have an expert with you? Did he look at the installation of the floating screed? What did you do with the edge strips of the screed?

No, an expert was not present. The edge strip was cut off when laying the floor, as far as I know.

Here I am curious now.... because we also have a massive noise problem in our "new build" apartment from 2018. We hear the footsteps or the stomping above us extremely loud. We even hear light switch clicks. Depending on the volume, we can even hear people speaking. But the kicker is that we can hear their bathtub or what they are doing in it in every corner of the apartment. For example, splashing as if someone is dripping water directly on my head or you can also hear when someone simply moves in the bathtub.
As I said, I am curious about the opinions here...... maybe I should open a topic myself.

I always suspect poorly insulated penetrations in cases like this. I once lived in a rental apartment from the 1950s. There were shafts that probably ran from top to bottom without any insulation. I could hear my neighbors peeing while lying in the bedroom.

Sound in the house spreads either as structure-borne sound or through the air. The former can be controlled with good construction quality, ensuring that structure-borne sound does not transfer from the floor to the wall and vice versa. Components are decoupled. Hanging clothes does not generate structure-borne sound (too little energy, too high frequency). Here, open doors and hard reflective surfaces (floor, walls, ceilings...) can facilitate sound transmission. Newly moved-in houses are sometimes still somewhat "bare" and transmit mid and higher frequencies excellently from room to room. Additionally, your entrance area seems to be tiled, so that room is likely to have substantial reverberation and clattering. If the rod for hangers in the dressing room is directly attached to the wall, loud hanger clattering is preprogrammed, without any defect being present.
Make sure you do not have hard opposing surfaces. Sound can either be damped or diffused. Then it will be fine.
Acoustic elements on the ceiling make a room cozy—e.g., from Ligno Trend.
Unfortunately, acoustic living comfort is often neglected in the planning phase.