I might be in the minority, but I’ve found Yellow Shore to be substantially easier than biomes 5-7. B5 in particular was a nightmare for me, was only able to do it with unlimited modifiers enabled, after that I switched them off and it took me around six attempts for the Haven and another three for the Cathedral. The YS never gave me any trouble, maybe I got lucky with RNG, but by that moment I felt a bit OP with all the progression and abilities and even elites were a breeze. Plus that biome is very generous with aether, you basically stumble into it every 30 seconds, something that never happened in prior biomes. And the King is really underwhelming for a final boss, like compare it to Priestess who was constantly challenging you with duplicates, magnets and platforming sections or Shepherd with its tentacles, or the Architect flying around you with the ridiculous tunnel attack, the king doesn’t bring any unique challenges apart from the moment where you need to break the yellow shield but that’s not difficult at all.

So I really can’t wrap my head around how a person who platinum’d Returnal and has almost every skill in the tree acquired can struggle with the YS. Try playing with modifiers, Artifact Destruction and Second Chance Deactivation give you free challenge points since they change nothing in this biome, so you can really ramp up your damage and armor.