It might be somewhat difficult to make effective arguments for this change in law. After all, the worker is doing things that the employer has told them to do while at work. If they do well, the employer profits. If they commit a tort, it seems to make sense for the employer to be liable. That said, we can make some arguments for this point of view.
The main argument would be that people should be liable for actions that they actually commit. America is based on the idea of individual rights and it should be based on the idea of individual responsibility as well. People should take responsibility for their own actions and should not be expected to take responsibility for the actions of others.
A secondary argument is that the employee who commits a tort is clearly not doing so on the orders of their employer. The employee who commits a tort may be trying to do what they were told to do, but they have clearly done it incorrectly. It makes no sense for an employer to be held liable when an employee does not do what the employer tells them to do. The employer did their part—they told the employee how to do the job right. If they provided proper training and the employee still made a mistake, it does not make sense to hold the employer liable.