Earlier quoted context omitted.
> DynamoDB, MongoDB, Elasticsearch, AWS Lambda, Azure, AWS, Azure Devops, SqlServer, Oracle, etc. At least with these individual tools, it's usually not your entire codebase written around that thing. For instance, you can generally switch from one database to another if they decide to overcharge you. You can even switch from one cloud service to another. In other words, they (usually) don't have you nearly as locked…
Of course you can switch databases, but in practice it is extremely expensive. That's a big reason why it is pretty rare. Why use a closed source tool and take on that risk when great open source ones exist?
in the case of servers: because open source servers literally can't support your scale of business. That's one of the few places where Open Source can never truly succeed: when you need a lot of hardware and the operating costs exceed any income coming in.
By that point it is a lot better to roll your own servers. But that is of course crazy expensive. Even other multibillion dollar corporations choose to leave some server management to places like Amazon/Microsoft.