The filesystem api would actually be a godsend regardless of whether if it would be limited to a single site owned directory or not. Right now we're limited to indexedDB, which is better than before where we only had localStorage, but persistence is a constant concern. I am always worried about whether the browser will just up and delete things. If they make everything be private and unsharable i.e. limited to a single domain, that includes no sharing between subdomains it would be perfectly viable.

The most important thing to note here is that we're looking to escape vendor control. A lot of people miss that. If browsers can get feature parity with apps that means no more app stores. no more app stores means more freedom of choice. Maybe that's not good for grandma but it's good for you and me.

There are a few decisions by chrome developers that I will never support, like a bunch of stuff in Manifest V3 but hopefully with other browser companies will provide a way around boneheaded, selfish corporate decisions while we reap the benefits of better integration with the operation system.