Incredible article -You should read:
‘Ahrefs wouldn’t be profitable, or even exist, if our products were 100% on AWS. If we used a cloud-only approach, our infrastructure costs would be 10+ times higher!’
https://tech.ahrefs.com/how-ahrefs-saved-us-400m-in-3-years-by-not-going-to-the-cloud-8939dd930af8