Add Camera Easy Thwart
It's like they are complete idiots. Smarter missiles are coming and one quick squiz before boom and "hey wait up, that's not a plane, that's a missile, oh, there's the plane". It boils down to cost efficiency and how much you can put up in the air. Smart Drones that use multiple methods to track targets, direct radar, water vapour density radar, heat and final visual inspection, all come into play for a smart drone, before it flies up along side the target, tells the pilot to land or bail out before blowing up directly over the cockpit.
Long range, compact, smart drones, will not be fooled by simple tricks and ramming speed is the best detonation method ie if you hit it hard enough to blow up, than it is the target you wanted and not a flare or chaff or a tiny missile.
Drones will keep trying to take out a target they miss, making those multiple passes you always see in sci fi movies and a manned plane with 4 missiles and a gun will simply lose when ten smart drones go hunting (keep in mind you can land them, make the safe, refuel them and send them up again, so guaranteed kill numbers become the norm ie ten fighter bombers come in so 100 drones are sent to take them out, likely twenty drones will come back to be refueled and sent up again, ten fighters take out ten drones but the next ten drones take out the fighters in a air space cluttered with 90 targets).