Do you have any examples? It seems like it's always been a grow-and-become-profitable-or-die-fast niche.
They need two traffic prices.... Fast low latency web traffic for the current 10 cents per GB. Slower more laggy CDN type bandwidth for like 10 cents per TB.
Edit: yes. (https://cloud.google.com/compute/docs/load-balancing/http/cd...) But it's more of a CloudFlare competitor—a distributed caching reverse-proxy with a 4MB object cachability limit. Costs $0.008/GB, which is cheap compared to a real CDN, but expensive compared to CloudFlare's "free."
And those rates are still in crazy territory compared to most alternatives other than Azure and AWS which have equally messed up bandwidth pricing last I checked.
I build caching solutions for customers that want to store their data in S3 or Google Cloud Storage, because the bandwidth prices at the big cloud providers are so out of whack that as soon as someone uses lots of egress (few TB a month or more), you can often cut your bandwidth costs by 80%+ or more by getting some dedicated cache servers to put in between your users and your cloud storage. That is after the rental and management costs for those cache servers are included.
(the reason for this rather than building storage solutions is that if the above fails you don't lose data. If you trust your abilities or service provider, building a multi-location storage setup with 3+ times redundancy that beats S3 etc. on cost by a large margin is fairly straight forward... But it's often easier to sleep at night if you have other people do the risky stuff..)