I agree that is not that difficult in Death March, but seriously, this type of criticism is pointless. If you found the game too easy, why don't you start limiting yourself like the mod basically does by itself? Try not to use skill points, don't upgrade your equipment, just swords for the damage, don't buy food, etc... People complain that they don't want to auto limit themselves but this is how the mod basically works, it doesn’t change enemies AI routine I guess. Witcher 3 is not a difficulty-based game, neither a gameplay-based game, the most important thing is the plot and the characters and for that, the gameplay of Witcher 3 for me is by far satisfying enough. I consider it one of the most fun and realistic action gdr gameplay.
The problem with recent games, though, is that they tend to give you so many possibilities that you necessary become overpowered at a certain point. Look at MGS V and its recent leaked gameplay: you have basically dozens of resources and possibilities (the buddy Quiet as a sniper seems so OP that looks more like a cheat) and this is a beneficial for the gameplay (more fun, more ways to play) but the game will be necessary more easy.
In my opinion, I still prefer "diversification" to difficulty.