* Gmail, Google apps
* Dropbox
* Slack
* GitHub
* Zendesk, Intercom, Salesforce or whatever
All of them are closed source. There is a lot of truth in the fact that one can only 'rely' on closed source products for non-infrastructure software. Only developers use open source products as such. Happy to be given counter examples.
Oracle doesn't want to compete with Slack, it wants Slack (and others) to be on Oracle cloud/databases.
See the logos under "More companies who love Slack" on the page:
Developers make it useful to customers.
It makes no sense to then claim this as a reason why the US Government shouldn't use or rely on open source. The US Government is large enough that if it were a company it would have major in-house developer cost centers.
That’s like saying a (mechanical) car by definition is a product for mechanics. Firefox.
I don't get your car analogy. Mechanical engineers had to design the car, and mechanics are needed to service cars. People who are either of those are free to do it themselves. What's the point?
A business owner can't just fire up Linux and watch their bank account rise. There is a specialist job there to connect the business owner with the service that they need - unless, of course, the business owner happens to be a technical specialist.