I live in a densely populated area. I see 250 distinct SSIDs belonging to about as many APs. 2.4GHz is basically unusable. People try to increase power of their emitters (I see some weird devices that emit way more power than they should legally be able to), but this is only making the problem worse.

Our flat is top of the building, we can assume middle is even worse.

We use 5GHz for our WiFi needs which does not penetrate through walls as readily which means we only see 3 other APs.