The post mentioned a wireless mesh network, so it sounds like the ISP/provider already has a bunch of wireless access points set up to cover the whole building. One of the problems with high-density living spaces is that there are only a limited number of communication channels WiFi can use, so if everyone living there also runs their own wireless networks they use up all the available channels and have to cross-talk over eachother, leading to everything slowing down.
For context I’m running KDE Neon on an Intel/Nvidia desktop. When KDE 6 first came out there were a lot of weird issues caused by the switch to Wayland like windows having flickering or strange rendering issues, but as the months have gone by almost all the issues I noticed at first have been getting fixed and disappearing, with only occasional new ones popping up.