I hope this paves the way for some kind of history syncing that can be used on Windows PCs also... With no Safari for Windows, I'm left to use some Chrome-based browser (Edge, Brave, Chrome, etc) and I'd love to be able to sync my browsing history over.
There is the major issue. It's a bit too little too late. Most Windows users have moved to 1Password, Lastpass, or other cross-platform solutions and won't come back to keychain now.
And this doesn't solve the browser issue. Passwords are great, but if you want to sync history/settings/etc from PC to iOS you have to use a 3rd party browser. No one is going to start using Safari who wasn't before without their history just for passwords that they could already do with any 3rd party password manager.
The Chrome bookmarks sync via iCloud extension Apple has barely works, it is finicky as heck.
Another problem is porting. There is no way to get passwords in or out of keychain without a Mac. All the others, at least the major players, you can export your lists out in a basic .csv file and imported into any other. So you get stuck with it; it's just not worth it for most who don't just use Apple stuff.