IMHO clothing CAN lot harder than quilts - but it really all depends on the pattern & details, just as it does with quilts
I started sewing my clothes when I was 13 and learned to quilt when I was 28
I did both for a few years, I sewed a lot for my girls when they were young, made things for their rooms, curtains etc but since then it's been ALL about quilting !!
I still make a (very) occasional jacket but it's quilts, purses and totes for me ... more fun to do !! (and you can't grow out of them ! LOL) :)