And lasers are supposed to be the answer? What can a laser do that more guns cannot, that's the question to ask.
Is it more portable? Well, no - yes, heavy autocannons do require VERY HEAVY wheeled or even moderate tracked vehicles to transport, but a laser system is going to require jaw-dropping quantities of electric energy, or chemical ammunition, or both. Those will be hard to transport, too.
Can a laser kill something it doesn't have line of sight to? Definitionally it cannot. In theoretical principle an autocannon can, but for all practical purposes it cannot.
Can a laser kill a drone faster than autocannon rounds can? Nnnot really. Autocannons DO have shell travel time to consider, there's the possibility of missed shots, etc; but the laser has to hold itself on the target and 'cook' for a bit. Autocannon shells can also be made into radar-guided bursting charges that take 'shooting down the planes' from a chance in hell, to the IJN wondering how in the hell their planes kept getting shot down!
What does a laser bring besides wanking "The Future" that an autocannon does not?
Well, it doesn't require hard ammunition, if it's not a chemical laser, I'll give it that. Does that make it more suitable for permanent emplacement? Yes.
But permanently emplacing anything is a great way to get it targeted and taken out. If you're moving the guns around all the time, even if it's only a few dozen meters to a new fighting position, that gets a lot harder. Sure, you can build out heavy electrical connections to a lot of places.
But let's look at another problem: the electrical grid is unreliable when you're under fire. Ammunition that you have stored in the back of a truck, barring the truck being blown up, isn't going anywhere except to the enemy. Ammunition manufactured in Britain, in Germany, in the United States (when we've extracted our heads from the Tangerine Palpatine's ass), in France and Poland, in frickin' Australia, can go to Ukraine and be shot at Russian drones, or helicopters, or planes, or in a pinch their infantry!
Electricity generated in Europe can still theoretically get to Ukraine, but unless there's an unbroken main power trunk between the power plant and the laser at the EXACT MOMENT it needs to start amplifying light, it's not firing. If the road connections between Poland and Ukraine get cut off, Polish ammo that's already in Ukraine can still be shot off. Ammo that was going to move by those roads can be rerouted and arrived delayed; if the electricity isn't connected at the exact moment you need it, you don't have it ever.
What does spending buckoobubux R&D'ing a technology that has only ever proven to be "workable" (in scare quotes) at large scales, at such ruinous expense that the Soviet Union and United States only ever bothered building a handful, bring to the table, over investing that money in designing an SPAAG for the 21st century? Something with newer, faster, more sensitive radars that can pick out drones flying low and slow, with lightning-fast turret rotation and semi-automatic operation?
Over developing a LIGHT SPAAG, based on the Browning M2, a module you can put on the back of an IFV, a truck, an armored car or "recon vehicle," and push out further than the bigger autocannon to act as the first line/tripwire?
You're right, in that the solution will have to be multilayered, and I never disputed that. In fact,I've been saying it. Those expensive, $500,000 interceptors STILL NEED TO EXIST, because the other guy WILL have $25,000,000 warplanes and hypersonic cruise missiles that will laugh at your SPAAGs. But SPAAGs are proven effective against the threat model that drones represent; yes, the Japanese kamikazes WERE effective when they were introduced as a desperation measure. They were also shot down in great numbers before accomplishing jack, and that was with 1945's radar-guided gunnery. 1965's radar-guided AA would have swept them from the skies. 2026's radar-guided gunnery should be even better.