"major release" != "major version number" Besides, Apple's major OS releases are executed like a major version number bump regardless of how others outside the

"major release" != "major version number" Besides, Apple's major OS releases are executed like a major version number bump regardless of how others outside the company do things. These bumps include deprecation markers and warnings for APIs with planned retirement. There's no technical reason to remove deprecated APIs (keeping them around forever) to support older apps.