Of all the mythic origin stories about the globe, Goths originating in Scandinavia is one of the less exciting ones to be proven correct.
DNA from unearthed car sized scales proving a giant snake carved the rivers and shape of the land would be something ...
I'm not so sure this study proves anything new, too. We always knew some Goths came from Scandinavia, that they mixed extensively with less mobile people in the regions they passed through during the age of migration, and that Gothic identity was (at least eventually) more tied to Arianism than to ancestry, so that when they became Catholic they stopped identifying as Gothic.
The real wild Gothic origin story is that the island of Gotland got overpopulated and they decided by lottery which 1/3 of them should leave.