Disney's movie "Frozen" has a lovable snowman named Olaf who dreams of sunbathing in the hot summer sun on the beach, not realizing that he would melt. Some things are just a bad match. It would be unreasonable to ask the California Coastal Commission to pay for bringing electrical power to the beach and for a very expensive walk-in freezer for Olaf. Imagine how that case would go. His attorney would argue that the 2010 ADA Standards for Accessible Design includes standards for making swimming pools, parks, golf courses, boating facilities, exercise clubs, and other recreation facilities accessible for individuals with disabilities. Obviously that would be a stupid case and any judge would throw it out.
However, a CAD drafter who has bad eyesight but can still do his or her job well is worth accommodating. Provided that the drafter has previous experience and is good at math and therefore does not need to rely on the CAD software's automatic features, s/he would produce very accurate work. It has actually happened before. The employer's accommodation was allowing more time to do projects because it takes longer to do math by hand and plot the points on the grid manually. It was not a significant difficulty or expense for the company and they received a tax break. With that said, it would have gone even better if they had bought a large screen computer monitor.
There are employers who discriminate against job candidates who used to have a disability but don't anymore. That's called a "perceived disability" which means that no disability actually exists. For example, a blind person who has been treated and now has perfect eyesight with glasses on is no longer disabled. There is nothing to fear but some prospective employers may hesitate to hire the candidate anyway. For that reason it's best not to disclose it. With that said, if the interviewer asks why a job ended or why there's an employment gap then the candidate will be forced to disclose it.
When that happens to me I just spit it out that I went blind due to a non work related injury and that an ophthalmologist treated it and now I see perfectly with glasses on, and if they keep talking about it then I show them my art portfolio. Nearly everyone gets it and moves forward.
To watch Disney's snowman Olaf sing about summertime click on this link.