That's not a precisely correct explanation either, though, because English 'j', pronounced /d͡ʒ/, is a single consonant sound (a voiced palato-alveolar affricate), not a sequence of two consonants. Though it's true that it's what English speakers would produce if you asked them to pronounce /d/ + /ʒ/ in sequence, because they always collapse into the single consonant. Not sure if that's also true in French.