I think but am not certain that Crowsnest is less 'ambitious' than MASC ever was.
You're not wrong.
Crowsnest by definition entails a helicopter platform.
MASC (Maritime Airborne Surveillance
and Control) was a deliberate change from the previous FOAEW (Future Organic AEW) to reflect the aspiration to do more than SKW/ASaC - and we're not talking FCs here, or mini J-STARS for that matter. It was based around the potential requirement on the airframe as much as the sensor / comms suite.