I know this about light frigs..... If they are in a fleet then you have to micro them. In an early rush of 8-10 carriers its still hard to get your light frigs in range before you get destroyed. Its really hard to have enuf light frigs with enough flak to defeat them. I realise you can do it with proper scouting but you would have to see this really early and focus on it or get carriers on your own. If he has already started then you are behind. Im not really for this obsessive/frantic scouting type of play. Ok ok Im exaggerating but you know what I mean.

But in all seriousness, the counter for carrier spam is easy. I just did this in a game, so it works.

Build a few fighter squadrons yourself. It doesn't need to be a massive swarm. 1/4 to 1/3 of the enemy's total number will do. Almost the entire rest of your fleet should be frigates, but throw in a few heavy hitters. (Like your capital ship and a few missile craft or illuminators.) Don't bother with many flak ships, if you do at all. You should have at least as many frigates as he has carriers. A few more than is better though.

Tell all your frigates to destroy his carriers. They shred them pretty easily, and they're faster than the carriers so they can't be kited.

Meanwhile if his fighters engage your fighters, it'll buy your frigates time to destroy the carriers. If the fighters engage your frigates, then their fighters will be shreded by your smaller force of fighters.

Meanwhile your few heavy hitters can engage his few heavy hitters. (He's spamming carriers, so there shouldn't be many.

I hope they only increase the speed and damage of light frigates versus carriers so that people who refuse to build light frigate can just continue to whine and lose. It might sound cruel but I have no pitty for those who can not addapt.

the reason they are protected so well in real life is because they are very important.  losing one means you lose a whole lot of force-projection capability, as you are not just losing a ship, you are losing 200+ aircraft.  even though a modern carrier could be sunk be a single WWII torpedo.

Well Like I said my main beef is real early on. I have successfully defended against over 50 squads with a mixed fleet and had him running and he had illums(halycon rules!). Still couldnt catch them tho. When your up against carrier spam its a bad idea to split up your fleet away from flak and ur halycon. Maybe they need to be further up on the lab list... say 4th or 5th tier?