In short YES, they could have. As anything else could have been implemented as custom post type and/or custom taxonomy.
But WordPress is a grown system – now 9 years old – and things are moving slowly to keep most stuff backwards compatible.
In short, with WP 3.5, the Links Manager will be moved to a plugin, as you can read in the trac ticket.
Related Posts:
- Building a Digg clone using WordPress?
- Removing custom post type from link search results
- Add / Remove Post Type from “Link to existing content” popup
- Taxonomy terms with edit/filter link in wp-admin, in the list of custom posts
- Website bookmarks as a custom post type
- Get_post_meta() won’t return value
- How do I display custom post types through a common taxonomy?
- Related links – from other sites
- Delete link on single-custom.php with redirection
- Linking to the most recent post in a Custom Post Type
- Link to full size post thumbnail
- Linking to Post Types from wp-admin
- Plain links in single-class.php and archive-class.php not working
- Highlight current post type when inside custom post type
- Adding link to dashboard sidebar, nested under custom post type
- Publish box in CPT remove ‘edit’ link
- Problem to get the link of the default ‘post’ post type like the orther custom types
- How can I generate a list of post-type specific categories?
- Post Custom & Taxonomy 404 error
- Why the custom post type links don’t work if not login?
- PHP Button Custom link [closed]
- Possible to limit internal link search to post types with Gutenberg editor?
- Custom post type Premalinks main page and details page
- Change CPT Edit Target Link for Admin List
- Replace the custom post type permalink
- How to change permalink structure off default posts and also CPT’s posts
- Pagination 404 on Index with custom query
- Add “Select All” to custom taxonomy
- post-per-page and offset not working
- Gravity forms multiple posts generated by one form [closed]
- Why are previous_post_link/next_post_link skipping some posts?
- Add tags to custom post type without menu link
- Display custom taxonomy on my custom post type
- List Categories (wp_terms) and count posts
- Post loop count is not in order
- Gravity forms how to display list of submitters on the post submitted page [closed]
- Add Previous/Next Buttons to CPT Single Pages Only
- Problem with $post_id object’s property
- get_post_types is not showing all registered posts
- How To Display A List Of CPT Posts In A Meta Box On Menus Page?
- Control content before and after custom post type loop
- Custom Post Types Archives and Single Pages not showing custom taxonomy data
- Custom post doesn’t show featured image
- Showing custom post type categories in the menu
- Displaying custom post types by category
- How to setup a single post page for my custom post type?
- Disable custom taxonomy on admin bar
- Conflict between Capabilities and Menu Visibility with Custom Post Types
- Custom Post not working as expected
- How to use a variable as a function name?
- What do the numbers mean at the end of add_action(‘save_post’)…?
- How to use next_posts_link/previous_posts_link for custom post types paginate?
- Getting WordPress Flexslider Item Number
- Designing a custom post type with a minimum number of meta fields
- Why does my taxonomy have a category style div id?
- Sorting posts by custom field value in array
- Custom post type paging 404 error
- Targeting categories in custom fields
- Display Only Certain Category In a Custom Page Template
- Saving Meta Data within Custom Post Type
- A meta box (in a custom post type) with two different type of fields
- Redirect to first child on Custom Post Type (without template)
- Assign CPT archive page attributes
- Move content between custom post types
- Custom post types problem
- How to get postname in custom page?
- Query custom post type based on post id and custom field value
- Pods CMS: How to add custom column to Adnvanced Content Type
- Custom post type, custom taxonomy, query posts only from taxonomy (children of)
- Creating Sections for Post Types
- Give each post type label a different color?
- page not found for single-type.php file
- Show list of custom posts with respective attachments?
- How to output an image or icon for selected check box in a custom post
- Check IF single OR multiple custom data has been entered
- Set a hard-coded page-template (post-type-archive) as home/front-page of my wordpress blog?
- How To Get Custom Post Type Category Title
- populate array with posts
- Displaying tags associated with posts in Custom Post Type
- Display custom posts randomly in custom taxonomy archive
- Using custom post type as taxonomy
- Transferring data to the end of a transaction with the Shopp Plugin
- Listing custom post types on archive page with array
- get_pagination not working on a custom post type query (using WP_Query)
- Show Posts to Author Only
- How to Make infinite loop of post
- Get custom post type categories to show up in menus
- WP_Query parameter conflict
- Create a comments template for custom post types
- Is it possible to add posts and images (auto resize) for custom post types with a script?
- wysiwyg editor don´t export paragraph
- Add custom attributes to a post
- Custom Type add Transitions
- How to make a meta box?
- Retrieving meta-box from a custom-post-type
- Cannot save Custom Post Type meta data
- Custom taxonomy page returns 404
- Custom post type permalink sends to 404.php
- Running a wordpress action when a custom post type term (taxonomy category) is changed
- Custom post types with categories in template