While there are protected classes that benefit from flexible working locations (people with some disabilities, for example), working from home in and of itself isn't a protected class, so there's no real chance for a lawsuit on that grounds.
> "because of your race, color, religion, sex (including pregnancy, gender identity, and sexual orientation), national origin, age (40 or older), disability or genetic information."[0]
Things like whether you are working remote or in-office, your political beliefs/affiliation, personality, where you choose to live, what color you died your hair, whether you re-heat salmon in the office microwave...these are generally not covered by charges of "discrimination" in the USA.
I think this is a pretty harsh framing. They directly ask for input from someone with expertise (indirectly making it known that their existing belief is not backed by relevant expertise). Then they state what their existing belief is. It reads to me like an invitation for someone to correct their existing belief.
Instead, they said:
> "Seems like a pretty obvious discrimination lawsuit."
Which is the difference between lazy inquiry and spreading misinformation.
That is also not true, because many locales in the US have requirements that reach beyond the minimums required by federal law.