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In general, unless the taxiway centerline ensures clearance from all aircraft types holding where instructed then this sort of incident will proliferate. The centerlines and holding point markings should serve to assure of adequate clearances provided that pilots use them as instructed in the Air Pilot or as instructed by ATC. Non-compliance equals negligence, does it not?
Please provide the quote from the 'Air Pilot' or whatever that says exactly what you must do in order to hold "at" a particular point? And what is the prescribed distance from the Holding Point at which you must be?
If you actually read the AAIB report I gave a link to above, and even provided an extract from, the AAIB confirmed that (then anyway) they could find no reason why a pilot must go "right up" to a holding point - and supported a pilot who again was "10s of metres from his cleared point".
In short, there are countless possible reasons why the BMI aircraft did not move forward... and they should not result in a collision (risk).
You seem to be advocating the sort of people who, if they have a green light on the road, feel it is in your right to drive and deliberately hit the car that has intentionally or accidentally crossed the red light.
Fortunately, most drivers, and hopefully all professional pilots (maybe yourself excepted if you are one) allow for unforeseen events, and don't taxi with not a care in the world and expect ATC and procedures to cover you. I am not suggesting the 767 pilot(s) were doing this - there are countless possible explanations for why they ended up hitting the 737. The causes are determined by the AAIB... not here.