In perfect conditions for Wi-Fi. I live in a high rise and the 2.4 Ghz band is hardly usable. My previous phone didn’t have dual band Wi-Fi and it was much faster on 4G than WiFi.
Plus, modern routers and APs often rely on band aggregation and so even with devices that have dual band, crowded airwaves will have a negative effect on speed.
Wi-Fi is very fast when I’m in my cabin in the countryside. But when I get home with the same devices, it’s barely usable.
You could argue that I need a better router with the newest protocol and gizmos but so far, even with new bands and protocols, Wi-Fi is still a competition of which router and devices will shout louder than their neighbors.
I would argue that the public needs to be better educated or at least saved from themselves with WiFi, however, nobody will be doing that. Having multiple lower-powered APs in a space can dramatically reduce how far outside of your premise the signal travels, and provide fast speeds indoors, however, it only takes one dummy to pick up a long-range AP, and put it in their apartment to ruin the wifi for everyone else around them.
Unless we start EM isolating apartments, or get everyone to start using modern lower-powered WiFi with multiple access points for coverage, things won’t change. I largely consider it to be impossible to fix WiFi in large buildings; especially established apartment buildings. No company is going to spend on 2.4Ghz and 5Ghz isolation insulation to be installed between units just for their renters to have better WiFi, and the general public as a whole… well, it’s basically a fool’s errand to convince everyone to do anything without government regulation, and bluntly, the government, made of the same idiots that make up the general public, isn’t any better and won’t be forcing everyone to “do it correctly”… so we get this dystopian landscape of WiFi for any high-density area.
IMO, new builds don’t really have an excuse not to, it’s a trivial additional cost to install while things are being built, putting AP hookups in the ceilings, and WiFi blocking measures in the walls between units, but they still don’t, because cost. They want to spend nothing and collect huge rent payments for basically squatting on a plot of land.