Well said. I'll also add, that with these networks, the sooner you can get traffic off your network the better. There's strong incentive to have your datacenter near these peering points. And since MAE-East was the first, it's been the largest as it's been snowballing the oldest. AOL's HQ was here, Equinix built their peering point soon after MAE-East, etc.

There's a great read about the whole area here: https://www.amazon.com/Internet-Alley-Technology-1945-2005-I...

As for AWS, I often see it repeated that the DCs are the oldest and therefor in disrepair. That's not true; many of the first ones have since been replaced. But there are services that are located here and only here.

But I'll also add, a lot of customers default to using US-East-1 without considering others, and too many deploy in only one AZ. Part of this is AWS's fault as their new services often launch in US-East-1 and West-2 first, so customers go to East-1 to get the new features first.

Speaking as one who was with AWS for 10 years as a TAM and Well-Architected contributor, I saw a lot of customers who didn't design with too much resiliency in mind, and so they get adversely affected when east-1 has an issue (either regional or AZ). The other regions have their fair bit of issues as well. It's not so much that east-1 necessarily fails more than the others, it's that it has so many AZs and so many workloads that people notice it more.

The underlying reason is more that by being in us east coast you have about equal latency for customers in us west coast and Europe. That's a very large population covered from a single site.

If you're building a single datacenter site this is where you start building first.