story
According to the AWS pricing example[1] 10 million requests per month on Lambda@Edge costs $9.13. The same thing on Cloudflare Workers[2] costs $5.00. So I would expect it to be closer to 2x. Although as you say there's a bit more flexibility with Lambda@Edge so it'll depend on your particular case.
I'm curious if your situation was different somehow that made for such a big cost difference between the two?
[1]https://aws.amazon.com/lambda/pricing/#Lambda.40Edge_Pricing [2]https://workers.cloudflare.com/#plans