I guess they are a regulatory requirement because all of the modern aircraft have to request special conditions form FAA and EASA to justify why they do not comply with these requirements.

For example for the Airbus A350;:

> The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These proposed special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.

[1] https://www.federalregister.gov/documents/2013/12/17/2013-29...