Illuminated partitions in the bathroom

I also had something different than the picture in mind. Install LED light strip in a track with frosted plastic cover into the drywall. This way, there are no problems with moisture, temperature, and patchy light.

Sorry if I caused any confusion.

So is something like this only possible with drywall construction?

Are unlit niches also only realized with the help of drywall construction?

No, that is also possible with wooden studs, masonry, or other construction methods. Drywall is proven, inexpensive, and easy to manufacture.

My wife and I are considering whether we want to have the planned partitions (1x next to the bathtub and 1x in the shower) illuminated.

I wouldn't do it. As nicely said

Yeah, it's quite trendy nowadays... or almost out again.

I wonder if it still impresses anyone (meaning on the builder's side) or if people think that if you skip it, it's social housing.

We have implemented this with us, even multiple times. On the one hand, we had to surround almost the entire bathroom with drywall (cable routing) and wanted to loosen it up with different heights, depths, and shapes. On the other hand, these niches are part of our "lighting concept."

In total, we equipped 3 niches (along with a spotlight at the tub and LED behind the mirror) with dimmable LEDs - so to speak, the romantic lighting (parallel/alternative to the conventional lighting). Apart from the material, of course, there is additional work during construction, which I would estimate at about 2-3 hours per niche for an experienced fitter - so it is not even particularly expensive.

Independently of the trendy feeling of the client, this results in a really cozy illumination of the bathroom and at the same time saves at least one piece of furniture, since you can of course also store towels or a few nice boxes with shampoo supplies in the niches.

When planning, be sure to consider in advance whether you want to use 12/24 volts; in that case, the power supply should still be installed somewhere.

Okay, we will see how the [GU] wants to implement something like that with us... There would partly be enough space for a dry construction pre-wall. But not everywhere... We would rather not narrow the shower.