Right, the situation with SO is completely different: nothing about SO stops you from just shooting back. Quoting myself:
...it would be a loss where there is no counterplay available at all unless specifically building to deal with it. Not 'this enemy is too strong, let me try again with different order/strategy etc', but 'it is impossible to touch this enemy without other tools'....
There are no special tools needed to deal with luddic path/SO fleets that they are untouchable without: they are just stronger than might first be expected, especially when compared to pirates. But all the normal ways to build a ship work just fine, as do making tactical changes to orders and how the player pilots. They are hard not just because of SO, but that many of their ships get SO for
free (with downsides that they as suicide ships mostly ignore), have more aggressive ship systems, have built in hammer barrages on top, and have unified reckless tactics.
...
Although preventing annoying harassing, boring combat and too much ships fleeing out of combat because of CR is a good point, then make High scatter amplifier with hard flux at 1000 be mutually exclusive with ITU/DTC/Advanced Optics. It drags kitting ships into danger zone. It also creates new need for Frigate hunter ship. Probably fast cruiser.
In this system I see stone/scissor/paper mechanic. Where Frigates are Dangerous to Capitals, Capitals are dangerous to cruisers, cruisers are dangerous to Frigates.
Another bold solution is, ask for better AI which is able to evaluate danger more analog way. So a bigger ship AI should bee able lower down shields, even under tickling by hard flux Frigate.
Having some mutual exclusivity could work, but I would prefer the graduated approach some others have suggested where the % of hard flux decreases with range. Or just get rid of HSA.
There are some elements of rock/paper/scissors in the game at present, but they are all pretty "soft", by which I mean that almost everything can hurt something else even if they are bad at it. This kind of change makes a category of ship that could reliably just not be touched under many circumstances.
AI lowering shields is really difficult, because I agree with you that there are lots of circumstances where the best thing for a capital to do would be to just ignore the beam frigate and focus on killing other things with its shield down. But there are also situations where that just means that the AI lets the frigate get hull damage for free, potentially for a long time, which would look really dumb to any player watching. Determining how the AI goes between these two extreme scenarios is quite difficult because its context dependent.