I am seriously doubting an allergic driver would be forced to take a passenger with a dog. Their immediate right to life trumps the ADA.

There's more interesting arguments to be made, like you can't ask the driver to provide proof of their allergies, and so on.

Does there exist such a thing as a life threatening allergy to dogs?

The rules are pretty clear that an allergy isn't a good enough reason to deny service, but it says that Uber should try and accommodate employees that don't want to be around dogs for whatever reason: https://www.ada.gov/service_animals_2010.htm

I'm not sure it matters if the allergy is life threatening or not. Again, you can't question the validity or scope of someone's disability under the ADA.

You need to read the rules more carefully: they mean Uber, in as much as it is in control of the rideshare service, can't deny people on that basis. The individual drivers can and their employer must accommodate them under the ADA.

If the drivers aren't employees and are self employed then as they are a business of less than 15 employees they can refuse anyone they want for any reason.

This type of compelled behavior seems like an oversized club to wield for the problem at hand. No individual should be forced to do something that will be harmful to them just because another individual belongs to a particular group.

No individual is being forced. Uber is being forced. Uber's the one that's gonna have to pay another $1 million in damages or whatever if they don't.

Fair enough. A lot of comments are talking about forcing drivers, even with allergies or phobias, to take any fare requested by a disabled person. It's definitely up to Uber to figure out how to comply and how to incentivize. Forced labor of individuals definitely isn't the way to do it, and is antithetical to modern principles of government.