The late game goes to shit because enemies don't get interesting, they just have their stats, poise and damage massively inflated.
The archers don't do anything fancy, they just three shot you with a constant stagger combo. The black knife Assassins aren't difficult, they just hyper armour through your attacks and tank the damage. The tree beast doesn't do anything new, it's just three of them in one area.
I was expecting this to happen in some places, but the sheer tedium of it really jumped out at me around the time I got to Leyndell and its sewer system. Again, Omen aren't memorable - they're just barricades of infinite stamina and FP in narrow pipes.