B-wings are slow, and bombs negate shields.
Bombs can very well eat B-wings.
I just want to make sure that everyone here understands properly how bombs work.
A Seismic Charge deals one damage, which means it follows the normal damage rules. If the ship has any shields remaining, at all, it will ping the shields. If there are no shields, then it will deal a damage card. No shield "negating", unless you mean it will remove a shield token...
A Proton Bomb will deal one faceup damage card, which happens irrespectively of any shields. But the Proton Bomb costs 5 points, and only does 2 hull damage in the best case scenario, so the amount of Proton Bombs you must hit a B-Wing with is usually 3, and sometimes 2. You might as well just bring 3 APTs, as you'll have a much easier time landing those than the bombs, and they'd be more effective - which is amazing, because that's APTs we're talking here.
Bombs aren't horrible, but it's the pair of Seismic Charges mixed into a Bomber swarm or dual Firepsray list that's making waves, used against swarms and Rebel slow movers. It's certainly not Protons used against elite slippery B-Wing aces.