Three years of my life were spent working as an underwriter in insurance where safe assumptions are made all the time. For example, a white collar job is generally less risky than a blue collar job. An underwriter of life insurance would deem it safe to discount more on the white collar proposal than the blue collar proposal without research because of the already defined safe assumptions. Another safe assumption would be a house with a pit bull is much riskier than a house without. So much so that the household with the pit bull would most likely be turned down for homeowners insurance based on this safe assumption.
The issue with safe assumptions is just that, they're assumptions. They're scenarios that have been mulled over by the actuarial department and a decision has been made that is deemed appropriate for the broad range of situations. However, using a safe assumption you've elected to forgo creating your own opinion in favor of the generally shared view. Let me repeat that, you have elected to give up your right to make your own decision for one that is provided. And this, is where we have a huge problem, especially when it comes to dog breeds and the discrimination that is coupled along with it.