The F-35 from what I have read needs on average 8 hours maintenance for every hour in the air, it’s that fragile. So I would imagine the F-47 is not any better. They are trying to get these planes to do way more than they should.
That's really low compared to even commercial airplanes. Those man hours are a fleetwide average of arming, servicing maintaining and periodic inspections.
That’s not fragile at all.
Besides, the F-35 has shown to be a very capable platform.
It could probably cruise the length of the Ukraine/Russia line and not get shot down.