Caporegime
MSI explains why not all Radeon RX 5600 XT can get 14 Gbps memory
https://videocardz.com/newz/msi-explains-why-not-all-radeon-rx-5600-xt-can-get-14-gbps-memory
As above this MSI excuse is dubious.
You have a choice to buy the chip ready-made on a reference PCB with the memory, in such case all you need to do is add a cooler and ship it with your own branding.
Or you can just have the chip on its own, you design your own PCB and you source your own memory.
I'm pretty sure you can get the chip on a reference PCB without the memory installed too.
To simply say "oh AMD just send out Chip + Memory bundles and that memory might not be able to do 14Gbps" is not entirely true and its a way to push the blame on to AMD.
If as it looks like MSI are just buying in ready-made reference cards and slapping their own cooler on them then yes you might have a problem, yet others who at least buy in their own memory will not have a problem, the problem is yours MSI.