Maybe we’d have a chance if you told us why you have that view in the first place.

You're absolutely correct. People have been trying for decades and it's never gone beyond toy deployments. Even scenarios where it would be critically useful such as mobile military haven't really made it work. The latency problem is unfixable.

(It doesn't help that people in this thread are confusing "mesh" with "collection of access points each of which is individually connected to a wired ISP", which is not a mesh.)

Why is it a pipe dream? It could also be something like roaming (in foreign countries), whatever - just a community mobile network that anyone can join.

If you're talking about wireless-only mesh and using it as the only form of connectivity, sure, you're right. If it's just another way to connect then it is very practical for use in high-density urban areas, but highly unlikely to be widely implemented as ISPs are the main distributors of the most suitable node devices and they are the ones with the most to lose if mesh is easily available.