At least for the "ATM at gunpoint" case, the bank is required to reimburse all but $50, provided that you report the incident promptly.
Regulation E of the Consumer Finance Protection Bureau (12 CFR Part 1005) governs electronic fund transfers. Section 1005.2 defines "unauthorized electronic fund transfer" as "an electronic fund transfer from a consumer's account initiated by a person other than the consumer without actual authority to initiate the transfer and from which the consumer receives no benefit". And there is an official interpretation that this includes:
Access device obtained through robbery or fraud. An unauthorized EFT includes a transfer initiated by a person who obtained the access device from the consumer through fraud or robbery.
Forced initiation. An EFT at an ATM is an unauthorized transfer if the consumer has been induced by force to initiate the transfer.
Although it's not quite in keeping with everyday usage, the context of the regulation makes it appear that "transfer" includes cash withdrawals.
Liability rules for unauthorized transfers are in Section 1005.6. In summary, if the "loss or theft of the access device" (which I assume would be read to include a forced usage) is reported to the bank within two business days, the consumer is only liable for the first $50 of the loss; the bank must reimburse the rest. If it is not reported within two business days, then the consumer is liable for the first $500. The bank must credit the consumer's account, at least provisionally, within 10 business days (Section 1005.11).
This rule doesn't directly address the case of forced use of a bank's online services or mobile app. I don't know if it would be treated the same.
Many banks offer "zero liability" fraud policies that go beyond what the law requires. Those may or may not apply to the situations you describe; you'd have to read the policy of the specific bank to know for sure.