Eh, “difficult” is relative. I’ve been playing through the single player story on Veteran and have progressed just fine. But I grew up playing a lot of flight sims (many that were far more complicated and difficult than this). In the world of flight sims, Squadrons is actually rather simplified and pretty easy.
In any case, as it is an actual flight sim and not an arcade shooter, I cannot stress enough how much I highly recommend playing it with an actual joystick. Playing it with a game pad or (God forbid!) a mouse and keyboard significantly hinders the simulator immersion aspect of the game. It’s supposed to make you feel like you’re in the cockpit. And a cockpit has a stick (or yoke, but I digress…).