Common sense is a thing and what common sense can tell us absolutely isn't an extraordinary claim.

Edit:

By the way, what do you mean by threat level here? And FWIW, here I could have used quotes without being rude.

Also: if you read that sentence again you'll probably find that it wasn't just the use of quotes but the sentence that as a whole that made it stand out as rude.

A baseline AWS account with MFA will not be taken over. That would require a credential leak or an IAM misconfiguration permitting access from some other account.

Suggesting it is an extraordinary claim, and would suggest an extraordinary threat to all AWS accounts. This seems very unlikely.