Just mouse and keyboard alone would make for a massive world of difference in difficulty. Even with aim assist, higher skilled players on PC will be able to react (turning and aiming) far faster than the best console players using a controller. Higher framerates just makes it even easier for PC players.
Basically to even things out, they need to go in and make the raids easier on console versus attempting to keep the difficulty the same. The hard part is attempting to make the console difficulty match the feel of the PC difficulty.
That's something hard to do. Usually games are tuned for console difficulty levels and thus feel extremely easy on PC. I find it interesting that this time difficulty was turned to PC difficulty levels.
Although if M&KB becomes more prevalent on console, the more correct terminology would be M&KB difficulty versus console controller difficulty.
Regards,
SB