Are LAN sockets still up-to-date? WLAN/wireless is the future!

The hardware isn't that expensive anymore. Fiber optics doesn't cost that much anyway, but copper has also become reasonably affordable. Running the entire network at 10 GB is currently exaggerated anyway, so a few corresponding ports would be sufficient.

Yes, I have at some places e.g. in the office (10Gbit). NAS, switches, etc. are connected to each other via 20Gbit (link aggregation). The NAS is connected via 20 Gbit, twice 10 Gbit, and three times 1Gbit for the different networks. Meanwhile, there are also cheaper switches. But I also have a 10Gbit router, so it also makes sense within vlans... My entire setup is from Unifi.

Not to forget the underfloor heating, with small spacing the water also blocks quite a bit, plus a concrete ceiling and not much gets through anymore.

For example, a Zigbee bridge on the first floor doesn't manage to get through the floor into the room below.

I would say you are playing in a different league here, far removed from what a normal user needs. I don't know what kind of business you run, but who on earth needs a 10Gbit wiring in the house? Normal users for streaming, etc., definitely not. May I ask what kind of internet connection you have?

I do not run any business in the house at all. It is purely private. Anyone who installs Cat7 or Cat8 today already has 10Gbit-capable cabling. I use it too. Especially with larger amounts of data such as backups, photos (processing raw data), that’s a whole different level. Also, due to the cameras, we have a certain continuous load on the network (separate network). This was not about the LAN cabling itself. 1Gbit is still fully sufficient today. Wifi is a supplement to the LAN. Therefore, everything in the property to cable and the rest to Wifi. In most houses, one access point per floor and one outside is enough. But not centrally, rather where the most speed is needed and where most clients are (living room, office...). There you have 5Ghz coverage. The 2.4Ghz radiates further. Just plan a few positions during construction. The cable costs almost nothing... Start with 2-3 APs and if it’s not enough, simply expand. Your Deco M3 has just 867Mbit (single) in the 5Ghz network. Modern APs are close to 2000Mbit and already achieve 800Mbit in the 2.4Ghz network. Slowly systems with Wifi 6 are also coming. Here there are significantly higher speeds. We have cable + Telekom + LTE for internet connection. Currently, only cable 1Gbit (with higher upload and native dual stack) and fallback to LTE are in use.

Wow, but you also deal with it professionally, right? Definitely a cool hobby :-) I know, my Deco isn’t anything special, but I barely have any devices that use 5GHz and it’s enough for streaming on my two TVs in the bedroom and guest/office room. The TV in the living room and the PCs are connected via network cable. In the office, it’s currently still connected via LAN to one of the Decos, but I’m going to install another network cable there. However, even with this setup, I currently get the full 200Mbit that I have as an internet connection.