Made specifically to plan out the shortest possible route between multiple cities using an in-built calculator akin to this:
https://www.youtube.com/watch?v=SC5CX8drAtU
It could become useful for some people…
Possible? Of course.
But not here. OSM at its heart is just a database, and there are many outside parties that build applications on top of it.
This would be another such application. Feel free.
I think several of the widely used OSM-based routers implement such a capability, see https://help.openstreetmap.org/questions/55994/traveling-salesman-routing