No, because exchanges in public markets never get to this point. Unless you're margin called, you're not put into a position where you forfeit your assets. Moreover that's still not an ultimatum where value simply goes from the customer to the exchange without any consideration - it occurs because the assets you borrowed from the exchange in the first place have been lost or exposed to great risk.

This is not about a do over, it's about the ultimatum being reasonable. If an exchange declared that you had 10 days to withdraw funds issued by, say, dividends, or you'd simply lose those funds with no consideration or equitable exchange, it would be sued (and successfully so).

Coinbase did not (and does not) need to allow trading in order to disburse the forked currency to existing customers.