It's only been languishing because the GOP stalled it's implementation. Yes, Biden's proclamation can be challenged. But, as you point out, that means the GOP has to openly say women aren't equal and should not be. I don't doubt they'll be willing to do so. But, this would definitely be the tipping point, I think (I hope) — especially since some on the right are also saying we should abolish the 19th Amendment. I mean, if they legislate that women should not have equal rights, how far a leap is it to expect them to go after our right to vote at all?