The Save as copy function can be used effectively to keep coherent formatting standards for all articles. You write a "master" article, with all the nicely formatted paragraphs, heading, photos and, by means of the "Save as copy" function, you create actual articles that you later edit and eventually assign tags to.
In this scenario having the tags of the master article tags automatically copied is irrelevant or not much useful.
We also recognize that there are other cases when copying the tags to the target article is indeed a useful feature. Therefore we will include this feature in future Custom Properties releases.
