First why I decided to not use WiFi at home:
1- Security concerns: I didn't want to invest so much time to learn how to secure my WiFi. It was 10 years ago, home equipment wasn't safe, and I had to learn from scratch.
2- Safety concerns: with baby and/or young children I felt I would rather not add RF generator inside my home. I know we are immersed in RF from everywhere, making some a few meters away is another level. I didn't want to add that. Just in case.
3- Network speed: 10 years ago, Ethernet was much faster than WiFi
4- Reinforced concrete could make dead spot in some rooms, what's the point of WiFi if I can't enjoy it everywhere or have issues?
Why I used Ethernet:
1- Rather easy wiring for my home configuration.
2- Fast and reliable
3- Security (neighborhood, not talking of Internet)
Why almost all rooms wired:
- Garage: my first noisy file server
- Two bedrooms out of three: Laptops / iMac
- Living room: gateway, main PC, printer, new file server, console, laptop, media player, guest laptop, ...
- Kitchen: laptop (after dinner)