This will eliminate the need to install a profile from the Developer Center in order to get developer betas, simplifying the beta downloading process. There is also an option for public beta testers as well who want to install updates with less hassle.
Note that this will put an end to the public sharing of developer beta profiles as installing a developer beta will require each person to be signed into an Apple ID linked to a developer account.
I don’t think so, in the screenshot of the iOS 16.4 Beta 3 in Software Update, Apple added a login button with Apple ID that has enrolled in Apple Beta Software Program (Public beta) and Apple Developer Program (Developer beta). That means they will stop using beta profiles and move to Apple ID to download future beta updates.