Perhaps that was meant as a reply to some other post rather than mine?
That said, while app makers can make decisions about what versions to support, there are some things that Apple influences, like, for example, when Xcode is used Apple makes updates so that when apps are created or updated then because of the updated version of Xcode the minimum supported iOS version can be higher than that which a developer might want to have. That said, as I recall, Apple still provides an ability to have the last compatible version available in the App Store for those who are on older versions of iOS, and I believe that it's up to the developer to make those versions still available (there won't be anything new in those or any fixes or any updates basically, and things might stop working here and there, so they might be pulled because of that).