The critical factor is whether you can concentrate your defenses in time to meet an attack, once you have detected that incoming attack.
Force concentration is a job for fighter jets. Most jets can fly at Mach 1, or even Mach2 (700mph to 1500mph). At which point, a 120mph Shahed-136 is basically standing still.
Different weapons for different tasks. The AA Gun is cheap and meant to be widely deployed across the whole frontline. Infantry could use them against other infantry (30mm airbursts will still wreck enemy infantry), and also rely upon those guns to protect themselves vs enemy drones.
Force concentration is a job for fighter jets. Most jets can fly at Mach 1, or even Mach2 (700mph to 1500mph). At which point, a 120mph Shahed-136 is basically standing still.
Different weapons for different tasks. The AA Gun is cheap and meant to be widely deployed across the whole frontline. Infantry could use them against other infantry (30mm airbursts will still wreck enemy infantry), and also rely upon those guns to protect themselves vs enemy drones.