Not quite sure about that, nowadays I require a couple of 20 bucks/month servers to have one CI/staging and one training/production deployments. I'm at the point where I practice CD as in "deploy each git-push to branchname.ci.example.com and run cypress on it" and still am able to deliver in half a day what the customer would expect to happen in two weeks.
And of course, baremetal provides a much better ROI than VMs/VPS/<insert glorified chroot/jail here>.
You seem to have gotten your deployments down and I really think that's good. In my own experience, though, managing your own infra always works well until it doesn't anymore. And when it stops working well, it crashes and burns and sucks up all the time. Going with managed services like serverless helps to get around that.
And of course, baremetal provides a much better ROI than VMs/VPS/<insert glorified chroot/jail here>.