Cloudflare has been attacking the S3 egress problem by creating Sippy: https://developers.cloudflare.com/r2/data-migration/sippy/ It allows you to incrementally migrate off of providers like S3 and onto the egress-free Cloudflare R2. Very clever idea. He calls R2 an undiscovered gem and IMO this is the gem's undiscovered gem. (Understandable since Sippy is very new and still in beta)
And, if you're in the same boat as someone down-thread complaining about Cloudflare's uptime in recent weeks, you can keep S3 + Cloudfront (or Lightsail Buckets + Lightsail CDN) and S3 + CacheReserve on R2, which is what we do, and flip between them with DNS.