This is an underrated point. The problem with AWS and those massive services is that they are "alive" and continuously evolving. In most cases it's fine and you don't notice, but when it goes wrong it can affect you and you have no control over when that is likely to happen.

In contrast with in-house infrastructure, you can make your stack as simple or as complex as you'd like depending on your needs (a lot of projects can get away with a handful of physical machines all configured manually, no Terraform/Kubernetes/etc) and you control when you make drastic changes that risk breaking things so you can plan them during a time when downtime would be the least damaging to your business.