Maybe it could be an issue with the level range. I feel the game well balanced with my char at 150 but same mobs destroys or two shots people at +300 looking at some videos.
Having played invasions, many many people dont level up health so they're a one shot kill already. It is a comical reality of how people play the game: never levelling their health pool.
We have figured out how to no hit Elden Ring. There's walkthroughs and guides.
We haven't figured out how to no hit the DLC. The walkthroughs and guides for it are being written now though. Once those are all up this whole refrain of difficulty will pass as people will be able to spoil any surprises and feel better about it.