You're right, the headline should clearly have read:

"Based on a DNA study conducted by Dr. Laura Cassidy of Trinity College Dublin and others, assumptions that most iron age Celtic societies were patrilocal have not borne out genetically, which shows that potentially there are time periods where matrilocality is more common, changing views of how women in ancient societies are viewed by modern people studying them, but this is all still early days as the paper has just been published in the science journal known as Nature and the peer review process still has to run its course. And even then, sometimes peer-reviewed science gets overturned, so we can't actually be sure any of this is true until a time machine is invented, which physicists currently think is not a practical possibility (although we haven't surveyed 100% of them on this)."

There. Accurate. Hmm... not all that succinct though.

I guess they should have gone with the title of the paper in Nature: "Continental influx and pervasive matrilocality in Iron Age Britain"

Everyone would have understood it!