Not the entire world but maybe enough of it.

I mean, think about the batshit idea of raiway transport in Europe. Like trains sound nice in principle, sure, it works on the scale of a mine or a shipyard to move things around, but using that to travel between all major cities (and even most villages) and countries all over? It would require laying thousands and thousands of kilometers of train tracks.

Or introducing electricity and phone lines, public lighting, and adopting various standards, metrification, putting road signage everywhere, etc. etc.

We've done a lot of large scale transformations. But to kickstart the process, robots need to be "good enough" without these infrastructure changes, and then people will see it and want the change. You can't start speculatively. It has to work first, and offer to work better if there is more infra standardization.