[m463]

Well, there is the Robustness Principle:

Be conservative in what you do, be liberal in what you accept from others (often reworded as "Be conservative in what you send, be liberal in what you accept").

the wisdom of that policy just accrues over time.

[1] https://en.wikipedia.org/wiki/Robustness_principle

[lonelappde]

Hyrum's Law challenges that supposed wisdom.

https://www.hyrumslaw.com/

Postel's Law creates debt that we pay interest on forever

Since Hyrum's law is a naturalist observation and Postel's Law is a suggestion, Hyrum's law is a more definitive truth.

[m463]

I can see that too. You end up possibly supporting a bug-compatible interface or other nonsense.

Amusing but unrelated I looked to see if that law was on wikipedia and clicked on this thinking it might be another spelling:

https://en.wikipedia.org/wiki/Yhprum%27s_law