[vessenes]

Native here: you’re correct it’s a weird sentence and turn of phrase in English.

That said, can/cannot is a flexible word in English and we could take it to mean “Anyone discussing the significance of JUMPSEAT [accurately] [should never] understate it.”

But I think he meant overstate in this case. Or maybe he hated JUMPSEAT, thought it sucked and put that right out there in the press release.