Originally Posted by
irishguy28
On TATL, AF/KL/DL/AZ operate an immunised joint venture, and therefore are effectively a single airline. As such, it wouldn't make much sense for them to differentiate as regards baggage policy and charges, when they operate in lockstep in all other matters.
They do, however, differentiate on seat selection. Delta does not allow advance seat selection on Basic Economy, but KLM does on Light Fares (same rules as other fares.)