New Jersey is having a great Cyp acaule year!! Visiting the old stands, we found lots in bloom and many juveniles.
Now North East Pennsylvania where we have a place, is not doing that great this year, the second year in a row we saw lots of juveniles and very few in bloom. But then it was a very long cold spell in that region and all wildflowers were really slow to come up.
Regarding the rare /endangered part - I have only shared the location of our stands with very few trusted friends. Many people don't realize that removing them from their specific habitat spells a sure death to the plant and might be tempted to dig them up.
And no, they are not that rare, if you know where to look, but I still consider them protected!