"why should i level to 105 again on my Archer when i already did it on my warrior?"
"Why should i beat Pokemon League again in Pokemon "Insert Title" when i already did it on my last run"
"Why do i need to kill the Enderdragon again on a new world to access expanded end when i already did it once"
"Why cant i skip all raid challenges on repeated runs if i already did them once"
Thats the Essence of your question:
"Why should i need to complete the caves again to access the lootrun If i already did it on another class"
See, exact Same Tone and mindset.
Now fr tho,
- It takes 5 minutes okay? Atleast If you know the cave and in the case you dont, good that you have to do them again.
- Its Basic Game Design, and its also Part of making a new class, If you make a "new Character", you should also need to meet the requirements for endgame content again, Atleast If it doesnt lake very long / didnt take very long in the other character
- You probably didnt play before lootrun update, but there is a meaning behind caves even If they dont Count towards a massive reward chest, they still give loot, and completion Meter from the class. Your approach is wrong If you Thing of caves that you loot while you arent in a lootrun as unnecessary and annoying