You’re probably right...phobias affect people differently. I think what irritates me is the idea of trying to accomodate all of those phobias in varying degrees under the ADA. Who would ever lose a demand for accomodation?
I believe the idea (and yes, there have been a lot of egregious abuses of the ADA, such as public places where there were always personnel present to help handicapped visitors get around, but they were illogically forced by Uncle Sam to put in expensive special equipment anyhow) is that the cost or effort of the work accommodation should not be exorbitant or prevent any necessary job feature from being carried out. So if you have a bad back, you won’t get an accommodation in a ditch digger job. It would apply to H1B’s and green card holders as well as US citizens.