No, you can't wear boots at all unless you have a matching helmet.
By that I meant curaiss and greaves. That has already been confirmed. PlayStation mag confirmed chest and legs are joined, and E3 confirmed helmet, gauntlets, and boots could still be changed.
Where did you see/hear that boots have to have a matching helmet?
Playstation Mags exact qoute, "clothing will be simplified, with outfits and armor sets coming as a single suit rather than separate parts." We already know this to be wrong, with visual evidence of separate parts.