There are certainly a lot of cons, yep. I feel like a lot of the arguments here are a bit apples and oranges, some people are getting really upset over it.
But sometimes, you just need a ton of bandwidth, compute, RAM, etc. and don't care about managed services.. I don't think there's a single major cloud provider that will give me a 2TB Intel DC SSD to use 100% of r/w for $20/m. And not being billed per-GB bandwidth is a massive relief for certain use cases.
EDIT: oh and also server buying/renting/installing is probably the smallest problem when running your own metal/colo or renting servers. a big use case for clouds is, data sharing between hosts via object storage/moveable disks, etc. which is non trivial on "bare metal/colo/renting" and that is just one use case.