It wasn't Army's job to protect Imran Khan, since he is making own decisions albeit threats that he is aware of yet his security wasn't fool proof, in fact it lapsed which brought a man with a gun close to him. And if anyone thinks that Military is behind this, then Military wouldn't want to make a martyr out of Imran Khan by killing him and neither would ever want to get blamed for carrying out an attempt on his life in public. This attempted murder is a backfire of emotional sentiments that Imran Khan is injecting into the Pakistani society through the British principle of creating a division like a wedge, closely based on divide and rule, but not exactly or entirely. Again, start connecting the dots since 2018, then April 2022 till now. The anger and frustration that Imran Khan has poured out vehemently has consequences, but not from Political parties neither Military as they don't perceive him as a threat of any sort. There is no reason to brace yourself for shocking news anymore as the lid of conspiracy theories has opened up. Go to media and get burnt out, then come back and start posting more and more hatred just like IK utters in his emotional sermons. You and like-minded individuals may think that Pakistan is going towards a big revolution where Military and Political parties will get a complete new overhaul. Both these entities are being cautious while Imran Khan may seem rampant but hopefully he keeps dodges the bullets that are aimed at him. A dead IK will be considered a martyr while a wounded IK will generate respect and sympathy. Both do not align with agendas of IK's enemies.
A 70 year old shot in leg with multiple gun wounds at close range may face loss of blood, but there are chances he will survive, even if the bone gets crushed, or the flesh or muscle completely ruptures. It has more chances to disable the movement of a person than kill him. The shooter almost fired in auto mode, that should have lifted the muzzle up, easier aiming for top body parts at around 100-150 m range, but the bullet struck leg/foot. If you see the video, you can see IK's head and chest were inviting targets, not leg.
On the contrary, all it takes is one sniper from around 1-1.5 km with the correct caliber and metrics to take on a stationary target (moving in rare cases, depends upon direction of travel). Army has many of those in formations. This even wasn't a repeat of LAK or BB assassination or assassination attempt. At tops, it may further strengthen the security cordon and make IK's long marches more cautious, security centric, time-organized and technology dependent in future.
Anyways, enjoy the media analysis, the trend of blames in news and by political parties, as well as the statements from experts. Its an open season for more conspiracies to brew.