IssueTracker

Tentatively, the annotation should be something use-case-specific like @OutlinedNewApi that allows alternative build systems (e.g. not R8/D8) to make their own decisions. We'll provide a default Proguard configuration for R8, but it's not guaranteed this will work as intended -- outlining is automatic in newer versions, but it may be disabled.

Just as an FYI, this was enabled in AGP 2 years ago (AGP 7.3 as far as I remember), ag/18426192, so for AGP users it might fine to just remove the rule for @DoNotInline. I like the @OutlinedNewApi to make it clear what this is for other consumers to handle it as they see fit.

This article from Morten Krogh-Jespersen suggests it wasn't (perma-)enabled by default until AGP 8.1, which is only <redacted>% of users.

Given the failure mode can include run-time crashes, that's not an acceptable level of usage.

I think you can still include a top-level proguard.txt, and it will be used by versions that do not support the com.android.tools format. E.g. Kotlin Coroutines library does this