Virtual collaboration tools are significantly reducing the barriers, but there is still no substitute for building professional relationships in meatspace. So doing something impressive in a field outside of the human network is an exception, not the rule.
Not surprising that an apparent American isn't as concerned about it as me, though. Let's all move to the US and then make conferences about how the tech industry needs more diversity. The conferences will be hosted in Silicon Valley, of course. There will be free catering and foosball.
https://www.google.com/maps/place/H-Farm/@45.554728,12.42898...
It's not that I'm in favor of only having one cluster, I've just accepted it as a fact of life. To some degree this has always been the case -- art in Florence, music in Vienna, etc. etc. etc. There are tons of examples.
I'd love for other major clusters to emerge, but sociological laws are as real as the laws of physics. It's no use to lament the inconvenience of gravity, and it's no use to lament the inconvenience of network effects. They simply exist.
Hand-waving pseudo science. Do you have anything concrete?
EDIT: serial down votes are nice. "Hey, screw this guy, let's down vote all of his posts in this particular thread".
> with no actual evidence?
There is evidence, look at the thread you're posting in. Also you could imagine what phenomena you might see when individual actors following personal incentives make choices. Maybe you could then ask yourself why centers of gravity sometimes seem to move around, and look at examples in history, and then why not ask yourself how being in a world with more affordable travel would affect things. You could then understand things about how the world around you works. But no, it's easier to cry pseudoscience and not have to think about things.
The period of glory for one local school was much shorter than you can grasp with a superficial familiarity with the subject. And even during that period, the "lesser" centers were also important to the history of art.