Do any regulatory bodies require ISO 9001 QMS certification from airlines or service providers?
No, there are no civil aviation authorities that require QMS implementation.

ICAO documentation (Document 9859) discusses the integration of other systems, such as quality and environmental management systems. There are advantages of integrations, such as facilitating data management and reducing redundancies.

For example, a QMS has many of the same documentation requirements as an SMS, so an integrated system is logical. However, not all operator benefit from an QMS, especially the smaller ones.