mperial escorts tend to have 1-2 turrets, cruisers tend to be 2-3, and Battleships tend to be 4-5. For reference, each Turret gets to shoot first to try to kill an oncoming wave of fighters/bombers, and afterwards, each surviving bomber squadron gets to make d6-T attacks against the ship, where T is the number of turrets.
Which is a rather round about way of saying that bombers will struggle with the heaviest targets, but can work quite well against lighter combatants, especially if massed. Torpedo bombers may work better - each successful turret attack can degrade a torpedo spread by 1 strength, and a bomber launched torpedo spread starts with 2 strength. Though of course the torpedoes then have to beat the ship's armor, so not exactly guaranteed damage, but that's true of most things in BFG.
To be clear, that's all just my admittedly basic understanding of Battlefleet Gothic, but the short version is that carrier tactics can work; we'd probably want hanger cramming, improved passive stealth, and maybe improved torpedos, but it could definitely work even before we get into crazier stuff like antimatter torpedoes. It's not a paradigm we necessarily have to pursue, but it could definitely work.