Workplace discrimination against disabled people is as at least as commonplace as it is illegal. The question is more how easy it would be to make the case against this kind of thing, rather than whether such a maneuver would be illegal in principle or in spirit.
Laying off people via wfh, irrespective of their disability seems to be pretty much in the vogue right now
Amazon is not known for obeying labor laws with any sort of regularity.