It absolutely should. Making the default "never prompt" would lead to websites prompting users to modify their preferences and change security settings. We do not want to normalize that behaviour. It would be a security nightmare. The defaults might be a little annoying for users (who can switch it to never prompt if they want to) but keeping average users who do want email or chat notifications safe online should take priority.
I don’t think average users want email or chat notifications.
And I don’t think web sites would prompt this as they don’t on Safari and that works out ok.
I think Chrome defaults stuff that Google thinks makes advertisers more money and Google more money. Safari defaults stuff that Apple thinks users want.
Chrome should default not to prompt. Safari estimates that no one wants this, and I suspect they’re right.