Much as I love peanut butter (and cashew nut butter), jelly / jam / preserve / conserve / marmalade / chutney is lush! A cream cracker is rubbish without a bit of butter and raspberry jam.
Why can we not pick both we dont have enough to make a sandwich who makes a jelly sandwich and peanut butter sandwich is fine but id prefere some jelly .
There's one type of peanut butter I've fallen in love with and will spread disproportionately to the jelly. Otherwise, I feel they're about even, and should generally be used together.