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Mo, I think there are psychological differences, probably. Also, body type influences what you're best at, or what comes most easily -- which often affects what you most enjoy.
But we get the same endorphin rush, I think, if we work out for long enough/ hard enough. It could be that some people don't lift heavy/ intensely enough to get that rush so they prefer cardio for that reason. I'm not sure.
I said I don't like running, but here's something funny -- I'll often choose a run instead of going to the gym. Why? 1. If I'm low on time. I can get a workout quickly by doing intervals and this is satisfying. 2. If I am not assured of getting equipment I need at the gym, I far prefer the run. (I hate it when it is crammed with the college boys and resist going then like you would not believe.) 3. Running gets me outside, where I would far, far, far prefer to workout. (I strongly dislike treadmill running and only do it when there's no choice to do anything else.)
Cardio/ aerobic stuff lets you go on autopilot and lets your mind wander a bit. This is a Good Thing for most of us.
Weightlifting demands more attention and focus. But at the same time it is very zen. You have to let go of your assumptions every time you go into the gym, have to be ready to humble yourself, have to listen to your body. Or face possible injury. It can be a sort of mindfulness practice. You have to be in the moment.
Either one of these activities can seem or feel "boring" to someone if they are in the wrong frame of mind. Or, either can become a kind of positive addiction.
Both have huge benefits (mental and emotional as well as physical). Ideally, we'd all do a balance. But....
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...ultimately, we should do the kind of exercise we love. Yeah, it's good to do this, that, and the other, ideal to have a balance -- but if you truly hate something, why do it?
