Frankly, I don't think it's practical to expect operating systems to continue to run binaries perfectly in perpetuity. It's an enormously burdensome expectation that holds development of the platform hostage.

Usually all it takes to keep one's software running on macOS is compiling against the latest SDK once every ~5 years. Depending on the nature of the app, source changes often aren't even required. As a dev I don't think that's too much to ask.

Apple unfortunately takes the opportunity of you compiling against the newest SDK to change and break all kinds of undocumented behaviors your app has been depending on, which almost always negotiates source code changes. If you’re lucky you’ll actually notice the changes; more than likely your app just appears more unstable and buggy to your users.