That's no how laws work. Not even remotely. Thankfully.
Consider you order somebody (X) to transport your pregnant cow. At the destination the cow arrives. It's not pregnant anymore and X refuses to give you the calf because... well, because he can do anything he wants.
That's theft.
https://blog.coinbase.com/update-for-customers-with-bitcoin-...
Basically, they said "if your pregnant cow gives birth, we will not give you the calf. If you want your calf, take your cow away from Coinbase and keep it on your own pasture!" And their customers heard it, said ok I'll keep the cow with you, and when the cow gave birth they cried foul.
Sheesh, this situation is 100% predicable because Coinbase announced it ahead of time.
Bitcoin holders need to take responsibility for their own holdings, especially when there is no FDIC or any type of assurance that your coins are going to be your coins.
So for Coinbase customers not tracking the fork news, this was a total blindside. This gives you 3 days to get all your coins out?
Not to mention if you used the "Coinbase Vault" your coins are subject to a 48 hour holding period before you can them into a usable Wallet. Then you have to wait for what was at some points an 8 hour transaction delay?
Also you need to figure out how securely set up a wallet, potentially order wallet hardware, etc.
No court would say that was sufficient notice.
And coinbase keeps the bch (as they announced), so the bird analogy does not fit at all.