I cant stand toxic comments like this. Just joking.
I think you are somewhat wrong by saying love of hardcore is bringing toxicity. Its toxic people that are bringing in the toxicity.
I love playing games like Rimworld on harder difficulties, because it creates emergent stories in to the games. It makes the game richer for me and it makes the colonies feel unique and i enjoy that quite a lot, but i dont feel the need to ridicule anybody for playing the game on peacefull.
In a way you are doing exactly the same thing than the "HC-players", but on the different end of the spectrum.
Also i want to say im firm beliver that not everything needs to be for everyone. If somebody wants to make a SHMUP that is impossible for people who have not played them before or kaizo Mario that only few people in small community can finish, its their artistic decition. I cant eat seafood, so sushi is not for me, but i cant resent the cheff who wanted to start a allfish restaurant, nor i cant blame my friend who loves to eat salmon.
How ever i do belive that aslong as the difficulty is not part of the games core design philosophy, it should be adjustable. Also there is no good reason to not add things like colorblind mode, adjustable font sizes and possibility to remap key bindings to games. Accessibility and difficulty are not the same thing.