easier for what? getting kills? obviously your opponent has less health..
on the flipside you also have less health so will also die much more easily than im normal mode.
imo hardcore requires more skill. when i moved from normal to hard i was just dieng every 2 seconds. it forces you to think about what you do, how to use the terrain, how to spot before being spotted etc. in normal i can just rambo and rack up the kills whereas in hardcore the odd bullet and your dead.
It doesn't require more skill as it comes down to one difference that becomes more apparent the lower (or higher) hp pools are. Higher HP pools reward players with more consistent aim, that can not only just hit the target but land headshots / upper chest shots more frequently. Lower HP pools reward who shoots first, with less emphasis on aim as you merely have to hit the target, not hit it anywhere in particular.
When you know you have good enough aim to take people on, you tend to start playing more aggressively, knowing rushing someone will probably have you come out on top. Hardcore undermines this, resulting in a game favouring a more campy style of play, which most skilled players aren't going to want anything to do with.
Then games aren't balanced for hardcore, it's an arbitrary change applied to the base game mode. So certain weapons become quite silly, some become quite pointless -- which otherwise filled valid roles in normal.
Play whichever you want, nobody should care what mode anyone else is playing on. Just know if you start dropping softcore bombs and otherwise declaring your mode superior in skill, people are going to call you on it -- I still remember a post from another forum about CoD4 when hardcore mode has just been introduced to the masses, I'm paraphrasing:
"The genius of this mode is in the name, they make the noobs playing the noob mode created for them think they're playing something superior"
Couldn't be anymore right.