Of course the bus goes around and around, it's been that way since the dawn of human history.
But you have this completely backwards with the chicken-or-egg thing. Israel (though not admitting these earlier ones officially) has been striking Syrian/Assad forces inside Syria for 6 months, a year maybe. Not Iranians inside Syria, but actual Assad forces, after said Assad guys had been firing stuff over the border. That was retaliatory by Israel, if admittedly a good deal larger and disproportionate (but "proportionate warfare" is a myth in the first place, the reality is you use what you have, just like Assad's guys do).
In this very-specific separate instance after Trump scrapped the deal, where the actual Revolutionary Guard got in on the hostilities, Israel didn't fire first. This is coming from ****ing Ben Wedeman of CNN reporting from Lebanon.
What are they supposed to do? Just absorb the rockets, pretend it didn't happen, not fire back? That's insanity. Doesn't matter they have way more advanced equipment and aren't at an existential threat from the Quds guys in Syria, you don't tolerate Iranian hostiles in their little-brother proxy state throwing temper tantrums over the deal in the form of actual tangible munitions across your border.