Originally Posted by
anabolism
My understanding over the years has been that OneWorld lounge access policy is status-based. That is, any OneWorld Sapphire member can use any OneWorld airline business class lounge when departing on a OneWorld flight, regardless of class of service. Likewise, any OneWorld Emerald member can use any OneWorld airline first class lounge when departing on a OneWorld flight, regardless of class of service. Since you do not have OneWorld Sapphire status, you were not eligible to use a OneWorld lounge. Separately from status-based access, the operating carrier provides lounge access based on class of service. Since you were flying QR J, you are eligible for whichever lounge QR contracts with for business class passengers.
However, I note that the
OneWorld lounge access policy does say that you should have access via class of service:
or you are traveling in a First or Business Class cabin on any oneworld member airline
As you concluded yourself, the access is either status based or cabin based.