But the cloud is different. None of the financial scale benefits are passed on to you. You save serious money running it in-house. The arguments around scale have no validity for the vast, vast majority of use cases.
Vercel isn't selling bread: they're selling a fancy steak dinner, and yes, you can make steak at home for much less, and if you eat fancy steak dinners at fancy restaurants every night you're going to go broke.
So the key is to understand whether your vendors are selling you bread, or a fancy steak dinner, and to not make the mistake of getting the two confused.