Israeli security is going to suspect everything is done by Iran because that is their threat model (and geopolitical incentive). If you asked enough security people in Seoul, they'd suspect North Korea. (Emphasis on suspicion. They wouldn't say it's likely Pyongyang if they're honest and competent.)
That's the nature of training focus on an enemy: you're constantly looking for and invalidating connections. Emphasis on active invalidation, which is the opposite of the scientific method, which starts with null hypotheses.
But scouting requires empirical feedback. If you have no way to invalidate your hypotheses, you end up in mind junk territory. Suspicions turn into assumptions turn into ground truths which fuel further suspicions. With each turn, they become increasingly baseless because that's what complex, unmoored processes do.
Reacting to a random shooting by looking to what Israel is saying about it is a signal that one has gone mind junk. (Not irretrievably. We all catch ourselves in idiot territory from time to time. I've criticized OP, so I'll put out an example: I initially suspected Iran was behind the Bondi Beach shootings because I thought high-powered rifles were illegal in Australia, that gangs wouldn't shoot up a synagogue, and I recalled Canberra expelling Iran's diplomatic mission because of something to do with bombing synagogues. Evidence showed that hypothesis to be flatly false. That not only means I need to reverse my hypothesis, but also be suspicious of future times I jump to conclusions around state-sponsored terrorism versus self-indoctrinated domestic terrrorism or more-banal criminality.)