The incompetence of tech support should not mean that I am harassing you. In fact, the poor management of the tech support and their workload should be a problem for upper management; these issues might get the tech support management in trouble or fired, these issues seems to be a more important to you than tech support’s response and quality.
You cannot possibly feel that this incident of tech support is a good example of the work of your staff, let alone a perfect example of tech support. I would like to discuss these issues with your boss.
In fact, your attitude and words are not those of conscientious and dedicated employee. I think that you need to retrained in what you function is. Threaten customers does not seem to part of your job, or anyone in a company.