Our internal uptime is 99.985 in production, we are fast moving and roll out changes every day, we run mainline kernels and all of our 350 odd servers and 800~ containers are running on completely vendor independent, open source software.
I'm not saying it's easy, but the middle man is there to help you if you can't find or afford up front good operational engineers, or to take your money because their advertising has made you believe that they are always the best decision.
We perform an in-detail yearly cross-cost comparison between AWS and our operated datacentre, the cost to run and maintain the same uptime, processing power (and yes we take into account spinning down instances at night etc...), bandwidth between zones, backups and customers and it really hasn't improve at all over the past 3 years. This year the review came back that our yearly expenditure on operational expenses would increase from approximately $500,000 (including human resources) to well over $3,000,000 a year. (Not kidding), the margin of error was approximated at between 10-20%.