There are several scenarios in enterprise companies where you have multiple releases of your product (and all of them are live at the same time) as well as the

There are several scenarios in enterprise companies where you have multiple releases of your product (and all of them are live at the same time) as well as the need to backport fixes to older versions. Git-flow is the answer in most of those scenarios and the only way to keep your sanity. What you describe is the happy path scenario.