Browsing Apple's reference documentation in the past provided full documents where you could see everything in context, with copious links to related functions. In today's reference documentation there is a document that covers, to varying degrees, the overview, with links to the individual functions. But each of those functions is in a separate web page.
It's incredibly difficult to discern groups of functions. In the "olde" documentation, methods for a class were divided up into sections at the top of the page, with links to the individual descriptions further down the document. Each class/protocol was a single document.
There's a third-party documentation viewer, Dash, that reads Apple's documentation and displays it in a manner that makes it easier to browse for specific functions.
From their website:
Dash is an API Documentation Browser and Code Snippet Manager. Dash instantly searches offline documentation sets for 200+ APIs, 100+ cheat sheets and more. You can even generate your own docsets or request docsets to be included.
Note: The SwiftUI Text view docs are a great example of what the Apple documentation should be, content wise. Lots of details, sample snippets. It's fantastic.
Dash brings those individual documentation leaves back together to give you the picture of the entire class as a single document, with the familiar grouping on the left side, broken out by sections. Obviously, all this information is coming from Apple's documentation, but it's being presented in a different fashion. It's much closer to the classic documentation viewing experience.
And while I use it exclusively for Apple's docs, it also integrates with other platform documentation. And you can add your own DocC as well.
Dash is $15. Which is a bargain for what it offers.