Mandatory Service Bulletins are paid by the manufacturer: Thales or Airbus in this case. Optional SB are paid by the user, and on the user's schedule. The maker tends to downplay the urgency, in order to avoid paying the cost. It takes a diligent regulator to correctly accept the maker's determination of mandatory vs. optional.
That certainly is not a fact other than what somebody negotiates in a contract.
The decision of mandatory is entitrely the regulators based only on the facts of the impact on safety. The manufacturer may place in the record any needs for urgency as they see fit. There has even been cases where a manufacturer's recommendation for urgency have not resulted in a mandated action by the regulator.
This is not about money, it's about safety relative to the original type certificate and any new useage data.About the only time money enters into this is the time for compliance factor.