its inevitable that large corporations become the backbone of internet infrastructure. its just too impossible to hold individuals accountable for network failures, physical or security - a corporation can be held liable, has the resources to fix issues, can implement large changes in standards (eg ipv4 >> ipv6), and can be audited (assuming the government actually does it). if the infrastructure was fragmented, it would be too hard to change and audit.
especially given how quickly internet technology is evolving, a distributed system just wouldnt work. plus you open lots of people up to exploitation through man-in-the-middle/on-path attacks - i strongly doubt a distributed infrastructure would have consistent and reliable security across all network nodes, considering how few people are actually aware of how computer and internet security works.