I'm not sure the memory bandwidth is "low" - assuming AMD use faster than 14gbps modules and a reasonable frequency it would have more bandwidth than the 3070 and about adequate for a card that was within a small percentage of the 3080.
That's why I put it in quotation marks... it's not especially low, but it's low compared to 3080's 760gbps, which will no doubt be the point of comparison for most people.