I would suggest reading the TAG's Web Platform Design Principles document, it does a really good job laying out why the web is different from mobile and native

I would suggest reading the TAG's Web Platform Design Principles document, it does a really good job laying out why the web is different from mobile and native applications and the reasons why some APIs, like client attestation, work in a mobile environment but would damage the web platform if they're implemented. For example, the WEI proposal violates the "It should be safe to visit a web page" principle (https://www.w3.org/TR/design-principles/#safe-to-browse https://www.w3.org/TR/design-principles/#safe-to-browse): When adding new features, design them to preserve the user expectation that visiting a web page is generally safe. The Web is named for its hyperlinked structure. In order for the web to remain vibrant, users need to be able to expect that merely visiting any given link won’t have implications for the security of their computer, or for any essential aspects of their privacy. For example, an API which allows any website to detect the use of assistive technologies may make users of these technologies feel unsafe visiting unknown web pages, since any web page may detect this private information. If users have a realistic expectation of safety, they can make informed decisions between Web-based technologies and other technologies. For example, users may choose to use a web-based food ordering page, rather than installing an app, since installing a native app is riskier than visiting a web page. I know a lot of savvy, non-technical users who absolutely refuse to install mobile apps on their phone except from the most trusted of sources, and I think this principle is a good structural framework for reasoning through why users still prefer the web.