the issue is this: you build a system that connects pieces of text in a certain way, and then someone steps in and tells you: hey that connection over there, you have to pay for.
but since not everyone will be willing or able to pay, your system is now broken.
therefore it needs to be made explicit that linking is not a publishing action that could trigger copyright enforcement.
[1] https://mimix.wpengine.com/wp-content/uploads/2018/08/On-Mim...
Would you use Mimix to utilize transclusion to edit the code of Mimix & to distribute it?
so i suppose that mimix will support transclusion, but it's up to the user to figure out whether transcluding a certain document is a copyright violation or not.
interestingly, iframes in html are an example of transclusion, so this is not exactly a new feature, and there are discussions on copyright about it:
https://www.plagiarismtoday.com/2009/04/07/is-the-diggbar-co...
https://policyreview.info/articles/news/eu-ruling-embedding-...
(funny how that seemingly contradicts the link-tax which started this branch of the discussion. i can transclude but i have to pay for a link?)