Pain is not the only thing that you can break or dispell against a genjutsu , any burst of chakra would free you from one like entering sage mode, activating curse mark or activating eight gates or even the raikage lightning armour. Now for the rpers that don't have such powerful jutsu or biographies you can use
1. Nagashi which can dispel b rank genjutsu and below , now the good thing about nagashi is that it is more or less the ideal counter to genjutsu that places the user under parlazyes.
(Raiton: Chidori Nagashi) - Lightning Release: One Thousand Birds Current
Range: Short - Mid
Chakra Cost: 30
Damage Points: 60
Description: This jutsu allows the user to generate non-focused electrically charged chakra from their body. Because the electricity isn't focused, it doesn't kill on contact, instead it only paralyzes. The lightning can be channelled through metal objects, as well as spread out into the air or ground.
2.Lightning Illusion Flash of Lightning Pillar: This can dispel genjutsu A rank and above and if you have lightning mastered and it is your specialty you can do it with a single hand seal. Another advantage is that it emits a blind light which you can use to blind your opponent leaving the door open for strikes.
(Raigen Raikochu) – Lightning Illusion Flash of Lightning Pillar
Chakra cost: 40
Damage points: N/A
Description: After performing the following handseals Ram → Horse → Snake → Tiger the user will then create a blinding light that appears to emanate from the users body and blind the target/s.
Now in my opinion if you were to counter an s rank , using nagashi which requires no hand seal and using lightning illusion flash of lightning pillar would break you out of it because the burst of chakra would be strong enough, and for forbidden i am not sure but try using the lightning illusion pillar twice , except in scenarios or genjutsu that paralyzes as the lightning illusion requires hand seal , so your best chance is nagashi twice i think.
Do you guys agree with this?