I largely agree... but to offer more nuance you need to know what the right amount of automation versus toil is right for your project. It's worth reading the Google SRE [0] books, especially the workbook, if you're thinking about running and operating a service.
Complexity is the enemy in software engineering as much as it is in operations engineering. Sustainable reliability is about doing as little as you can get away with to achieve the reliability results that make your customers happy. That does mean following the advice of TFA and avoiding going straight to k8s for a small indie site that could be deployed with a simple Ansible/Puppet script. However it also means defining what your targets are and having indicators so that you're not relying on your gut instincts either: aim for 60% toil, 40% automation at first. Whatever the right balance is review it regularly as you scale your project up.
You can do a lot with a couple of beefy VPSs and a solid database these days.