I tried getting into flight sims several times. Started with IL-2 and also tried Microsoft FS, MS Flight, Falcon 4.0 (or maybe Allied Force, I don't remember) and a bunch of other military ones. Basically they're all boring as fuck unless you're willing to spend time learning how to do shit. Stuff from PMDG is absurdly accurate and is actually sponsored by Boeing itself.
If you're into WW2 and early Cold War era planes though then War Thunder is your best choice right now, I'd say. Dunno how accurate the sim mode is because I only tried arcade, though. Still, way more players than you'll find on dedicated flight sims.