Very true. You want to try to get a channel nobody else is using, not real possible now days. Part of the reason dual band routers are getting popular. Gives you more channels and 5G does not pass though walls as easy which is good and bad depending on your needs.
It is quite a challenge to find some place that you will not get interference from someone else and this can change as time goes on as everyone plays the same game of chasing the most unused channels.