Which internet Wi-Fi mesh system?

I also work a lot on my NAS. Also with larger files. Data throughput in the LAN is important there

I can see that in the LAN, why not. But how does it look mobile in the house via WLAN?

17 APs. Almost everywhere 5GHz coverage (also in the garden). Here you really have to control the networks and transmission power. Due to the many APs, there are always only a few devices on one access point. Because of my concrete construction, many APs are necessary. My LAN in the office is 10 Gbit. Connection to the NAS and the switches is 20 or 40 Gbit respectively. I already mentioned that my network should/cannot serve as a template.

No, I didn't want a hardware list, but what kind of data you send over your WLAN. Which type of application and what data rate you actually need.

Yes, you are right, I am actually a standard user

about our house: the semi-detached house is being built from sand-lime brick with concrete ceilings.

Of course, I will try to connect as many devices as possible to the LAN.

For the Wi-Fi, good coverage is important to me so that there are no dead spots, but I do not need extremely high transfer rates (100mb+ would be enough) because I do not have to download extremely large amounts of data on mobile.

We will probably take fiber optic from Vodafone with 500mb

wifi call, WhatsApp, quickly checking emails, tablet surfing, etc. run over Wifi. But there are also several users in the house sometimes. My Wifi never shows more than 50% utilization. All stationary devices are connected via LAN.

which access point has Gbit in the 2.4 GHz range?

I haven't done a brand review now, but actually all with 802.11ax. Or at least many.

And that's not duplex

Of course not. WLAN is never duplex.

only theoretical

Also correct. But even at 25% actual data rate, a lot remains.

So everything stationary to LAN. Install enough APs.

Also correct. Anyone who knows wireless uses cable. I just wanted to argue against the prejudice "5 GHz is good, 2.4 GHz is bad." However, the somewhat better APs always have both anyway, and lately sometimes 6 GHz as well.