(2) is not a problem if you enact equivalent civil rights acts in every state. There would be plenty of political support for doing this today, including in the Sunbelt - which there wasn't in the 1950s.
I think “equivalent” would be the challenge here. When people need to know at all the nuances of what bathroom and restaurants they’re allowed to use, and what train cars when business or pleasure takes them across state lines it becomes a pretty large tax both for the individual and for interstate commerce at large
The bathroom issue is especially silly. Just mandate that public restrooms have to also include gender-neutral single-occupant bathrooms, that anyone can use as they desire.
Yes, but then achieving that mandate across the country becomes O(N) of states, all within the low bandwidth legislation process of state houses. Much simpler to just do it at the federal level, and still legitimately justifiable wrt interstate commerce imo
