You're getting downvoted, but here in a populated but not very interesting part of Pennsylvania there must be 15 different banks or credit unions with brick & mortar offices within 10 miles. I lament that not everyone has this degree of choice, but it's not a fantasy.
There may be an online-only bank somewhere in the USA that's app-only, but I wouldn't know. Every bank I've ever encountered has a very functional web site.
We have an app only bank in Canada called WealthSimple, but hardly the only choice.
The problem here seems to be that people want the free accounts and low fees of app only banks, but still want the costly things they got rid of that make those possible like branches.
There may be an online-only bank somewhere in the USA that's app-only, but I wouldn't know. Every bank I've ever encountered has a very functional web site.