The general guideline that most businesses follow regarding pay: How much value do you bring to the company?
Being disabled or not, really isn't part of the equation. If you're wheelchair-bound, but your work, more specifically, your decision-making, can make the company 10's-100's of thousands, millions of dollars, then you are going to receive higher compensation than someone else who might actually cost the company money. Yes, there are entry-level workers that are needed to operate the business, but actually cost the company money. They are a liability. If you happen to be seen as a liability, then good luck trying to get a raise. As a general rule, the "decision-makers" are the people making the higher wages and have some leverage for pay raises.
The only thing you can do in this situation is obtain more training to become more valuable to the company in a "decision-making position", or find another position in another company that will see you as an asset rather than a liability.
I totally understand this viewpoint that there can be staggering huge disparities between the compensation that a CEO and the average worker at many companies make. How can this be fair? It almost seems criminal. However, CEOs are the ones making the decisions that guide companies through all the ups and downs, they are the ones approving the decisions of people below them, they are the ones with the most value to the company and shareholders. The rest of us poor grunts below them are just disposable cogs in the machine. We don't add value. Sure, the company "propaganda" machine keeps telling us we are "valued team members", we are "family", as a means of making us feel loyal, but when it comes to leveraging for wages, then it becomes more clear that we can be replaced with a newer person at a lower wage.
Sorry, I've been working at a huge corporate health system for nearly 40 years and have seen a lot that has made me a bit "jaded", angry, and wise.