Whether it is still enshrined in ecclesiastical positive law is irrelevant. If it is of Divine Law it is binding. In the past even the Holy See has invalidly attempted to dispense Divine Law so the fact the Holy See is not enforcing this law at present is of no great theological significance.
The blog “feminine genius” reacts to WDTPRS on chapel veils, from Fr. John Zuhlsdorf of "What Does The Prayer Really Say", is a response article, apparently a response to a response to a previous article which had been posted here. It gets a little complicated, but following along in the discussion brings up some interesting thought.
One interesting thing for non-Catholics to note is that the Roman Catholic Church had originally required that women cover their heads when attending worship services, but in the past half century when women's head covering was declining in use all over the Western world, the Church took the requirement away, and left it up to personal opinion. Since headcovering wasn't required, apparently many just quit and didn't take the time to see the benefits of headcovering (as in many other Christian churches, I think). The author of this blog reminds his readers of his opinion:
To be clear, I maintain that there is no longer any obligation under the Church’s law for this, but I think it is a good custom that recommends itself for various reasons.
Read the whole discussion at the linked title above.