Yes it is fucking hard but the game gives you all the tools to beat it.
And I am pretty sure a lot of people dont explore to find the DLC upgrades.
I agree with this on games like this, leave it up to the players how they want to enjoy your game
Honestly I don't care if people enjoy some sort of God mode and just blow shit up
No. The game gives you shit ton of options to make it easy already, adding a difficulty slider is the opposite of what the game wants player to feel and achieve.
Use NPC or skill summons, get help from other players, level up, use throwables, respec and make an OP build, do some side content etc...
Asking a difficulty slider on games like this is like asking for horror movies to remove all scare and horror elements.
If someone does not want to bother getting better or finding the options to make things easier (that are extremely easy to find or use), then the game is not for them, that is all. And good news: there are thousands of other games to play.