With all due respect, you’re a small indie developer, and the situation is different when you make a browser used by millions of people. Apple does do whatever it wants, but sometimes it (wisely) realizes that what it wants is people to not be upset that people’s favorite app is broken in the next release of macOS, so occasionally steps are taken to ensure that doesn’t happen. This ranges from committing to SPI for longer than it is necessary for Apple’s own use, to putting in bundle ID or linked-on-or-after checks, or in rare cases reaching out to developers directly.
The target for this comment is developers like you, but those who are less familiar with the platform than you are but of similar import. Those are the ones who will read this and say “wow Firefox says this is how to make my app fast so I should do it!!1!” and what is going to happen is either they’re going to use it wrong, because they aren’t really experts on how locking works, or they’ll copy the code of of Firefox and their app will break in a future OS release while Mozilla will update their code in July.