Just cuz the strongest dude in the verse has no illusion resistance feats and cuz he couldn't release himself from KS doesn't mean is suppose to be anything, that was not the first time Almighty failed to counter something lol, Ichigo's attacks, GT, Antithesis, it was even said that he could deal with Almighty cuz he could interfere with his clairvoyance, this is a anti-feat for Yhwach. Narutoverse on the other hand has illusion tiers and even characters with powers to release themselves from illusions can fall for several ones and even those with eyes to see through illusions are still vulnerable to certain users's genjutsus. Six Paths level Rinnegan allows one to counter jutsu like IT, which is above any genjutsu in the verse, even Itachi could simulate an entire lifespan inside his Tsukuyomi, not let KS is a big deal. Somethings do never change.
Regardless, let's see how EHF deals with this :)