That is a good way to never ever ever use a feature again. "Frightening Message: This website wants to do something scary. Do you want to allow some bad thing to happen to your computer?" That is how lay people, i.e. the people needed to mass adoption, read browser requests for Geo, storage, and other permissions.
It would be better to have sane and safe defaults in the browser, rather than pester the user. Would cookies have worked if the browser asked for permission on every website?
Browsers like Chrome do it with geolocation for example. If it is required for the user to get a certain service they want, what's the "scary" part? You can say no and use the parts of the site that work with it, or yes and get the extra functionality. Like with geolocation.
It would be better to have sane and safe defaults in the browser, rather than pester the user. Would cookies have worked if the browser asked for permission on every website?