It's the unfortunate reality of software, but it's not an immutable law.

The Microsoft example is important. I've never been a fan, but I stand in grudging respect for what they've accomplished with their products as far as backwards compatibility goes, which has significant and enduring value.

Emulators are another example of how software can be long-lived with the right attention.

Personally, I think we have operating environment conceptions all wrong. We continually pay for or fête new versions and thus incentivize change for change's sake. We might do better to respect or even pay for continuing compatibility.