Hello!
Long ago, WordPress linked to attachment pages by default whenever a user inserted an image into a post. The Origin extension is helpful for users who have old posts lingering with this effect.
But the automatic linking is no longer in effect. For the off-chance such a page is reached, the “noindex” robots value is practical enough to fend off search engines. If no link exists to such a page, it’s unlikely a search engine will find it. So, Origin won’t do much for new sites.
There are some technical aspects where having “noindex” is helpful, such as filtering post types early. WordPress created exclusions for the attachment
post type about 80 times in its code, which is inefficient and prone to mistakes.
Also, WordPress is finally considering to rectify their mistake of WP 6.4; practically, Origin’s functionality will be shipped in Core, albeit not as elegantly. I can’t entirely agree with this change because it takes away the user’s ability to still display attachment pages.
Lastly, Origin shouldn’t be relied upon: There may be errors in the query or database that can lead to the failure of redirecting users to the original post or attachment URL. The “noindex” option, shipped and enabled by default in TSF, isn’t affected by such issues. So, both working in tandem is the best solution.
Concerning SEO, I don’t believe much ranking value is to be gained in 301-redirecting from attachment pages, if at all. I find that the value lies more in accessibility.
I think this covers everything. Cheers!