At long distances the small cross section of the drone requires tight focusing (expensive optics) or a high power, preferably pulsed laser (expensive laser) or both.

Not impossible but many times more expensive than the drone

Lasers won’t effectively work, it’s a two part equation, detection and targeting. To neutralize a target using a ground-based laser, you need an enormous power, and still it won’t penetrate a high distance/altitude in the sky, environment factors also to be considered. The detection part is even harder, these small 8in drones are almost impossible to detect unless you can hear it, aka it’s over, because they can fly at 250km/h, too small to be visually detected, acoustic sensors will fail to detect them, and radar will miss it as a false negative since it’s the size of a bird. I have seen some systems trying to combine all that to detect them plus AI for flying pattern detection, but they are far from being reliable in practical applications.

At very short distances and with a lot of power, perhaps. Despite what we see in movies laser beams diverge. And then with distance it’s harder to track moving objects precisely to hit the same spot long enough to melt it.

At that point might as well spend the money to use a kinetic weapon with basic tracking and ballistic calculations.

The practicalities of using lasers are covered in some depth on the Naval Gazing blog. First part here:

https://www.navalgazing.net/Lasers-at-Sea-Part-1

Powerful enough laser and accurate enough targeting system is easy to say, but not easypeasy to do. Dumping thousands of Joules on a tiny moving target is much easier to do with explosives.

Lasers imo don't really have IRL advantages over machine guns and rockets, and their line of sight nature is a huge limitation.