Those who talk/ask about re-routing at the flight-planning stage aren't fully aware of the operational realities of a longhaul operation.
If pilots were to ask dispatchers to route them around all the forecast areas of ISOL/OCNL CB activity that is in every SIGWX chart, there'd be absolute bedlam in every dispatch office. Some airlines even persist in choosing a route that takes you straight through an enroute cyclone/hurricane/typhoon.
It falls to the flight crew to assess the weather and order enough fuel to allow them to divert around individual/clumps of TS cells as they encounter them enroute; if your planned route takes you through an area of forecast ISOLated Cumulo nimBus, then you'd expect to uplift enough extra to go around one or two cells - not hugely inconvenient. But, however, if your flightplanned track looks like it will go through an area of OCcasioNaL CB, then it's time to think of taking a decent extra amount, in case the forecast is accurate and you wind up quite a way off track.
Some system failure or multiple failures of an extremely complex nature has befallen the crew on this occasion; I personally would very much doubt whether lightning had any contribution to play. My money is on probe icing or a dud ADIRU. The QF crew were fortunate enough to have been in day VMC for most of the event - which made their excellent handling of the failure that much easier. Night IMC would make it an entirely different proposition.