Right now, any lawsuit against me can be dismissed on summary judgement because even if my software causes harm, that's not a legal wrong to the extent I've disclaimed liability.
If you adopt any fact-specific standard for liability, that needs to be adjudicated in a trial. The legal fees alone would surpass the actual liability.
That creates huge leverage for the party with more resources. That kills hobbyist open-source development, since if your project takes off but a large enterprise finds it defective, they can threaten to sue you to enforce the "warranty" you were required to give.