But how many companies are never going to have scaling issues, and also have the resources to hire a good in-house sysadmin to manage their servers? And sure, maybe you have somebody on staff who can handle the sysadmin duties now, but what if they leave? Do you still have the resources to maintain your own servers?

The author's advice is good for basically one scenario: a personal hobby project run by somebody who already knows they would prefer to run their own servers instead of use a cloud host.