Not necessarily, the canopy is basically a non-targetable subsystem; it's entirely possible to get the hull down to 0% without having a single crack in it, or have it blown up on an otherwise almost intact ship. It all depends on where you take fire. I think there's also an element of randomness on whether it took damage or not during emergency drops too. At any rate, my hull's down to 90% and I just had the first cracks form. I've seen others fly further and longer with canopies in a much worse state so I'm not about to go panic mode and turn back - I just need a few thousand ly more to reach the self imposed secondary goal of my current trip, then I can turn back. Should be fine - it's the bubble that's dangerous to fly in
At any rate, thanks for the good wishes