Web NFC:
> Status of This Document
> This specification was published by the . It is not a W3C Standard nor is it on the W3C Standards Track.
— https://w3c.github.io/web-nfc/
> We oppose this feature and will not implement it.
> We do not believe a permission prompt is a sufficient mitigation for the serious security and privacy risks raised by this specification. In addition, we think exposing direct hardware access to the web is a bad idea and compromises the device-independence of the web platform.
— https://lists.webkit.org/pipermail/webkit-dev/2020-January/0...
> We believe Web NFC poses risks to users security and privacy because of the wide range of functionality of the existing NFC devices on which it would be supported, because there is no system for ensuring that private information is not accidentally exposed other than relying on user consent, and because of the difficulty of meaningfully asking the user for permission to share or write data when the browser cannot explain to the user what is being shared or written.
— https://mozilla.github.io/standards-positions/#web-nfc
WebUSB:
> This specification was published by the Web Platform Incubator Community Group. It is not a W3C Standard nor is it on the W3C Standards Track.
— https://wicg.github.io/webusb/
> WebKit declined to implement several APIs, including WebUSB, due to concerns over fingerprinting
> We have previously stated privacy concerns, thus the concerns: privacy label. We agree with Mozilla's security concerns raised in their standards position issue, thus the concerns: security label.
— https://github.com/WebKit/standards-positions/issues/68
> Because many USB devices are not designed to handle potentially-malicious interactions over the USB protocols and because those devices can have significant effects on the computer they're connected to, we believe that the security risks of exposing USB devices to the Web are too broad to risk exposing users to them or to explain properly to end users to obtain meaningful informed consent. It also poses risks that sites could use USB device identity or data stored on USB devices as tracking identifiers.
— https://mozilla.github.io/standards-positions/#webusb