It may help everyone to know that there are only about a dozen channels in 2.4 and about the same number on 5 GHz available.
Regardless of the application, or service, every wifi router has to pick a channel, and is competing for time on that channel with any other router on that channel. If you live on a home with a yard, you probably never feel this congestion. I live in a modest apartment complex, and in 2.4 GHz I see about 24 routers on 2.4 GHz. The two most congested channels have 6 and 10 competing signals. Also these signals overlap, so channel 5 actually takes up 3, 4, 5, 6 and 7.
The story is better on 5 GHz, for sure. The story is made even worse by services like Xfinity’s public wifi service, which is enabled by default. Those routers take 2 channels / router. Shame I can’t post images on this board, because you’d see the problem immediately. Lastly, many routers have a really horrible habit of using either the first, or last channel when set to "auto." So that means you see them all bunch up.
Again, I’m not selling anything. Wifi analyzers on Mac, PC and Android are all free. If you are curious, go look.