Inconsistent macro require behaviour

It is my understanding that a namespace has to :require-macros itself to have its macros accessible automatically but this no longer seems to be accurate.

Given this minimal example

I would expect a warning for lib/foo since demo.lib has no :require-macros for its macros and the demo.test did not use :include-macros or :refer-macros.

Compiling this via the build API does in fact produce the expected warning but only iff the demo.lib CLJ namespace was not required anywhere else.

Enabling the (require 'demo.lib) in the build.clj causes the warning to disappear and the code uses the macro properly.

Some popular libraries (eg. devcards) do not self-require but still work if the macro file was at least required somewhere else.

Is this intended behaviour or just accidental?