Most $10MM ARR startups are running on two medium T class aws instances behind a load balancer at $35/mo plus another small server for accessories (redis, message queue, etc) and then a sql backend. That's something like $200/mo for infrastructure, you never need to maintain the hardware and you have the option to autoscale at any time to support $100MM ARR.
Plus you get access to backups and all the other tools and products that are constantly being released. Not having to hire an IT guy at $1200/mo to maintain your physical server and tend to it's networking rules is a significant savings over a developer-managed aws/gcp instance. Plus all the cloud interfaces are standardized so you can just hire someone to come through and fix/upgrade your infrastructure.
Using a home-spun physical server means months if not years of undocumented tech debt for the next guy who comes along to have to maintain whatever kludges were installed long before he/she ever showed up. I just got done converting a bunch of physical servers over to the cloud and spent a year unwinding seven years of technical debt and now the dev/qa teams can actually spin up a new test environment in under 30 days (closer to 3 minutes).