There's a reason why those who made GitHub sold it to Microsoft. GitLab can sell itself to Google? After all Google too runs things like GMail "at a loss".
Also you mean Linux is successful because it is delivered "at a loss", and you can't compete with "free"?
"Microsoft basically wrote the book on it."
Oh no, they were already old stuff when Gates used them. There's a reason the Sherman Act was written in the XIX century.,.