I thought they were declared illegal and forcefully destroyed, but I wasn't there. Growing up in the 60s/70s my neighbor had one that apparently survived the "blight" or emerged after. It was old and since died so I suspect it survived rather than emerged.
Some can survive. It's just a rarity. We had two of them in my town when I was a kid. I used to walk to them with my grandfather and collect chestnuts. They were full grown adult trees. I think they died at some point in the 90s. I also think somehow in Michigan there's a grove of 600-800 of them. But this is down from the 4 billion that used to exist. 🥹