Mostly people will just cancel their holidays or agree a teleconference because getting flights on that route at short notice is too difficult.
Flying in/out of unfamiliar territory is a known risk. Whether the 737 MAX series is higher risk or not is an unknown risk because of insufficient sample sizes.
Hopefully some statistician will start tabulating P values so we can see if the confidence intervals overlap or not. Treat this situation like a new "better" drug for X where 2 users died in quick succession. Is there enough evidence to take it off the market or not? AFAIK, nobody has (yet).
>If the delay's long enough to actually see parked aircraft brought into service, it'll largely be the same crews flying older 737s anyway.
Sorta. On a Canadian airline, Westjet, the MAX is flying routes that are too far for the regular 737s without a fuel-stop (by my estimates). I'm booked for such a flight in 2 months. I'll get to learn what happens. I would have been happy to fly the MAX8 based on the current lack of evidence for grounding.
If there are, they'll have to wipe the dust off of them, and send type-rated crews into territories they're not familiar with day-to-day.
That, or defer maintenance of the existing fleet.
I'm unconvinced that this is the safe resolution, but that's what will happen.
At least the US and Canada allowed planes in-flight to land, instead of making them turnaround and come back anyway via non-revenue ferry flights.