All the clothes for M4, and M4 itself, has these huge bulbous looking things for shoulders. just totally unatural looking.

is there a way to fix those things?

Rerigg it or the morph brush. Shoulders have never been good on any figure IMO. Of course neither is the butt, talk about huge and bulbous!!! How about the flat pancake thighs? Or the huge dent in the side of the hip in the leg side to side? Then there's the paste on toast. And NO ANUS, so the poor guy is not only emasculated, he is constipated as well. :lol: 

Edit:  Except of course for Antonia, she has nice shoulders, hips and all.  :)

Then there's M4's ridiculous upper arms. And how his lats and shoulders turn into stretched silly putty when his arms are raised overhead. The last DAZ male figure with a realistic, posable physiognomy was Mike 2. So much for the “unimesh.”

M2 was a favorite of mine as well. I liked D3 for his general shape. Some of M4's rigging was nice and no magnets was a plus to me. But still just not a realistic figure, legs were too long (as usual) Which would have been ok if the scaling had worked. Resetting all the scaling was just too much work to bother, since I never get around to actually rendering anything anyway.  :)  Nice mesh though, almost pretty, in a mesh sort of way.

I have heard it said that he is hard to make clothing for? Why?

Won't stand still for a fitting. Yo-yo dieting. A confirmed nudist....

.... But something is not right with the M2 upper chest, I am just saying....

M4 has awful shoulders, I agree with OP.

has anyone done a shoulder morph that looks normal ?

M4's biceps are also a wreck.