Cloudflare is a US-based company that does MITM attacks on all traffic of the websites that it protects. It's part of how their DDoS mitigation works.
Many people still use large US-based mail providers such as Outlook or Gmail.
Many large services use AWS, GCP or Azure. Perhaps there are ways for the NSA to access customers' virtual storage or MITM attack traffic between app backends and the load balancer where TLS is not used.
Of course, in principle, a cloud provider could tap in anywhere you're using their services – ELB (load balancer), S3, etc. I presume they could even provide backdoors into EC2 instances if they were willing to take the reputational risk. But even if you assume the NSA or whoever is able to tap into internal network links within a data center, that alone wouldn't necessarily accomplish much (depending on the target).
There's also significant aggregation of traffic at handfuls of service providers amongst service categories, all generally HTTP(s) type services too ... Mail, CDN, Video, Voice, Chat, Social, etc. Each of these are still likely to employ Load Balancing & WAF.
Most WAF/Load Balancing providers have documentation about when/where to perform decrypt in your architecture.
How many Cloudflare sites are just using the Cloudflare wildcard cert?
From there, plenty of 3 letter agency space to start whiteboarding how they might continue to evolve their attack chain.
You might be thinking of DNS-over-HTTPS (DoH) or DNS-over-TLS (DoT).
There's also DNSCurve.
From what I remember, only DoT uses ECH
https://media.ccc.de/v/chaoscolloquium-1-dns-privacy-securit...
You can easily test this: dig @8.8.8.8 https pq.cloudflareresearch.com
A nationwide invisible firewall, with man in the middle decryption and permanent storage of all unencrypted data. All run by the major backbones and ISPs.
How would that work?
In a way it is the perfect solution from a Govt perspective. Other countries have systems at this scale and larger. China for example.