Requests for permission to send notifications are one of the most grating website behaviors, second only to auto-playing videos. Earlier this year, Firefox started experimenting with denying them by default, and now, Chrome is following suit. There's a flag in the Canary build that blocks all notification requests, only allowing notifications from sites you intentionally approve.
The flag has been there for a while, but previously, it didn't work. Accessible by navigating to chrome://flags/#quiet-notification-prompts, nixes notification request popups entirely in favor of a small icon in the omnibar denoting that the site wants to send notifications. You can click the icon to enable notifications, but otherwise, nothing will happen.
It's live now, so if you're brave enough to use Chrome's Canary channel, you can go test it out for yourself. We don't know when it'll make its way to more stable channels, but hopefully it'll happen soon.