Why don't we have a single registrar for all TLDs? Why don't we have GitHub as the single repository for ALL software in the world? My point is that sovereignt

Why don't we have a single registrar for all TLDs? Why don't we have GitHub as the single repository for ALL software in the world? My point is that sovereignty, innovation etc. are valuables which centralization can't deliver. "Monopolies will maximize profits and therefore, under-supply the product" is Economics 101. So, yes, economics of scale and network effects do encourage centralization but there are counter-balancing forces. What we need is protocols that allow a sliding scale as opposed to non-interoperable silos. DNS, TCP/IP, Git delivered exactly that. While GitHub has the scale and network effects, plenty of people are happily using GitLab, BitBucket etc.