And what about the Ahvaz military parade attack?
Seems to me it did not take place on a main road removed from rugged border terrain, nor did it target a large convoy armed to the teeth.
Troops participating at parades do not carry munitions in their weapons.
What about the Imam Khomeini shrine and parliament attack?
Very soft targets, genuinely incomparable to active military units.
What about the assassination of Iran’s head of nuclear research institute using AI powered machine gun in the back of a peykan in Karaj?
Not carried out by separatist terrorists. Also foreign intelligence agencies were involved to a far greater extent and far more directly.
The AI-powered machine gun story isn't proven, and Shahid Fakrizade was martyred not in Karaj but at Absard which is located past Damavand to the east of Tehran (in the opposite direction).
Those aren't valid analogous examples.
Bold of you to assume it would be difficult to an attack unsuspecting convoy,
There's no precedent of this kind in western Iran, other than perhaps during the early years of the Revolution i.e. at times of war.
or that these “local terrorist grouplets” don’t get assistatnce from foreign intelligence groups.
I made this assumption?
A handful of cheap explosive quadcopters could have killed 25+ soldiers operated from 2KM+ away.
...but didn't, because it does not correspond to the modus operandi terrorist grouplets claiming to represent Kurdish Iranians are known for.
Reason doesn't need to be technical feasibility by the way, it can be strategic and/or political, such as insufficient anticipated resilience to the necessarily ensuing counter-escalation. Simply put, the probability of a major attack of this kind against the shown convoy was close to nil.
To cite a somewhat extreme and disproportionate example (but the basic idea is similar), the USA regime "could" theoretically fire nuclear weapons at Tehran, nonetheless Tehranis aren't spending their lives in bunkers.