Now that the potential for multiple pitot heads to be offlined by a single meterological phenomena has been clearly established by the recent spate of incidents, the current system, shown to have no redundancy to this catastrophic failure mode, becomes a single point of failure in the safety analysis and as such will have to be addressed.
I don't agree with the presumption that such a single point failure need be presumed catsstophic.
The idea is that you must have enough barriers (layers of cheese) in place to make it extremely improbable to end up catastrophic. So what we are looking for here in the investigation are evidences of other layers of assumptions that might have been at play here.