The trouble is that this centres the fan chart on the mode of the distribution (the single likeliest outcome), and not necessarily on the median (the value that divides the outcomes, ranked by size, exactly in two) or the mean (the sum of the outcomes divided by the number of outcomes).
This means forward supply partners (from distribution through to end customers) likely went into a panic ordering mode today to increase inventory and put in safety stocks in case some parts go on allocation.