How can drones that take hours to arrive be a threat?
Now, we can't know yet exactly what sort of drones Iran is using here, or exactly from where they we launched, so there are large error bars. But that's where "hours" comes from.
The attack involved a lot of drones. Hundreds. Dealing with hundreds of drones with manned fighter aircraft is dubious and possibly a terrible mistake: committing and exposing high value assets for what is, militarily, scutwork.
Fighters don't carry enough gun ammo for the purpose, because ammo is heavy and the guns fire it very rapidly: typically there is only a few seconds of gun ammo capacity in a fighter. Air to air missiles are too precious to use on these targets: they're needed to defend against high value threats and can't be wasted on these crummy, militarized model aircraft from Iran. Also, these drones fly at relatively low altitude, so defending fighters must operate at low altitude and low speed over foreign territory, which is problematic for many reasons. Finally, the drones aren't easy to find because they aren't great radar targets, being small, low altitude, and mostly made of lightweight composites: it is unlikely they can all be detected and engaged quickly enough.
For all of these reasons and others, manned aircraft are poor counter for this sort of attack. Despite this fighter aircraft were used. It was reported that the US, the RAF and the IAF all used manned aircraft to bring down some of these drones. But as you know, many still reached Israel. There, cost effective ground defense did most of the work.
For good reason at the time.
With no after the fact knowledge a hybrid attack with drones that may or may not scatter chaff, may or may not include or be timed to occlude larger threats.
Dealing with drones alone is a poor use of fighter pilots. Having eyeballs in the sky along with "just in case" weapons is smart defensive tactics.
Post game is when armchair coaches can call out whether it was neccessary at that time.
This may also be cover for an attack from a different direction.
Indeed, they do seem to be painting a target on their heads.
Even without that, they could still rely on cameras and old fashion navigation.
in a false flag operation drones which take hours to arrive can be a threat