So you render all this on the server, and then the client does what, or are is this only targeting static pages?
React does not have shadow DOM
And I wish that was truly the case. Sadly half of all HTML written is to support presentation.
The Model can be generated from db schema or vice versa. You don't need to know SQL. The Model informs the ORM (Object Relational Mapper) how to create/read/update/delete (CRUD) your objects to/from the database. The model also validates your data for you. The field is 255 wide? Then 256 chars throws validation exceptions automatically, and so on.
The view is generated by reusable components on the server. Small reusable components ultimately assemble into a full page. Hundreds of components that do everything imaginable exist already.
With no code at all, they Controller wires them together using the Direct to Web (D2W) rule system. In fact, if all you want is an admin interface to do CRUD type operations on your database, you won't need anything beyond the hello world D2W application. These rules allow you to make sweeping changes throughout your entire application. Want to change every component that handles text input in a form page? Create one rule:
100: task = 'edit' and attribute.className = 'java.lang.String' => componentName = "MyNewEditStringComponent" [Assignment]
Or override with other components as appropriate
105: task = 'edit' and attribute.className = 'java.lang.String' and session.user.isAdmin => componentName = 'AdminEditString' [Assignment]
WebObjects allows you to maintain a level of state that no other web based MVC can match. You can nest your tables of data as deep as you like, paginating and sorting any of them at every level. No other web framework can do this. Period.
You only need to learn WebObjects to be full stack.
There is no interchangeable "standard" for that for the same reason there is no "standard" for almost anything in technology: different requirements, platforms, styles, projects, etc
For one thing, HTML was originally designed for read-only publishing. User interaction was gradually added over time.
For another, if you expand the scope of HTML to entire widgets, it'll become an incredibly bloated language. At a certain point, it needs to be building blocks rather than a pre-built solution.
Why don't Legos come with cars and boats already built in the box? Because some people don't want a car or a boat, they want a plane.
You might get some pieces that lend themselves to a particular purpose (select box, blockquote, etc.), but the language is not highly opinionated about what you do with them.
That's not true as generally as you've phrased it. Rendering HTML on the server is very useful for certain kinds of sites, like blogs. It allows you to generate pages that can be cached and behave like static pages (with appropriate, static-like headers).