This is a professional eBusiness forum and since XML and the related technologies are just that, technology this post is perhaps more relevant on technology and IT related forums like the W3 Schools forum, Sitepoint forum etc.
XLink summary:
"This has been an extremely brief look at the XLink technology. It has been around for quite a while, and some people
think it will revolutionize internet browsing."
Source: Robert Richards (2006): "Pro PHP XML and Web Services." page 159.
My bolding.
Yes it takes time before technologies become understood and even longer before they become standard. It took 20 years before object oriented programming were understood by people outside the SIMULA community. When Samalltalk were implemented in the 80's, OOP took off.