The go devs decided against this since they didn't want to build a highly optimizing (read: slow) compiler, but that is missing the point of developer ergonomics.
Most people nowadays ban building with warnings in CI and allow them during local development. But “CI” was barely a thing when go was developed so they just banned them completely. And now they are probably too stubborn to change.
Q. Why can’t I have feature X?
A. We thought of that already, and your opinion is wrong.
Q. But basically every other language in existence supports this. And it makes development easier. We would really, really like it. Please?
A. Apparently you don’t get it. Here’s a pointer to a 15 year-old post on a mailing list where the first time someone asked for this, we said no. Your opinion is wrong.
Sounds like we agree!