That's the current meta though is the thing and it could change.
There's a plausible world where drone-aircraft are reliable enough at missile evasion that a decent strategy is to get in close and use the cannons because your entire airframe is much more attritable.
There's even a plausible reason to do this: opening a weapons bay to shoot a missile generally reduces stealth, and not hauling a bunch of extra rocket motors and mass around could make you lighter, faster and with better engines to do it.
That's the current meta though is the thing and it could change.
There's a plausible world where drone-aircraft are reliable enough at missile evasion that a decent strategy is to get in close and use the cannons because your entire airframe is much more attritable.
There's even a plausible reason to do this: opening a weapons bay to shoot a missile generally reduces stealth, and not hauling a bunch of extra rocket motors and mass around could make you lighter, faster and with better engines to do it.