According to Claude when I asked it to audit one of our Python applications, there are scenarios where Brolti can be used only when some Python library detects that the C library is installed on the system. So your Brolti-ness can depend on which machine your code runs on. Ymmv, it didn't look to be a practical possibility in our code so I didn't probe further.
These chat bots always hedge like that. They will never give you a straight answer, it's always "depending on version and build configuration and system configuration".
Investigate yourself. Read the documentation. Grep for brotli in the source. Don't blindly trust a chat bot when it says it "might happen in certain configurations".