For me, bonking seems to be more about what I eat before a ride rather than what I eat during the ride.

Conventional wisdom says that you can only process 250-300 calories/hr when you're exercising heavily. The ride you've linked appears to have taken 5 hours of pedaling, covered 60 miles, and burned 2000 calories (I'd use kJ = kCal; Strava's calorie estimates are always a bit high). If you ate six 240-calorie Clif bars that would be 1440 total calories, which is only a 560-calorie deficit for the ride. I regularly do 2-hour rides where I burn 900-1100 calories and eat nothing, so that sort of nutrition would be unlikely to make me bonk.