I agree with the premise. Though, there's one more issue/potential reason not to endorse people using the clipboard for passwords, and it's not that malware wil

I agree with the premise. Though, there's one more issue/potential reason not to endorse people using the clipboard for passwords, and it's not that malware will grab them from the clipboard. It's that many non-malicious programs will regularly query the clipboard for legitimate reasons, but what they do with that data may be insecure. For example, think of how Pocket checks the macOS/iOS clipboard for URLs to add to the Pocket list.