Sorry to say, but the Sami finds have often been misenterpreted in the past, mainly due to political reasons. When the archaeologists of the past found remains of complex societies living up north, and whose culture was unified as far south as Dalarna, this was interpreted as non-Sami. First of all, the Sami of the time didn't live that far south at all. Second, the sami culture was oppressed in the political climate of the era, and for people to admit that the sami had been there just as early as the "Swedish" settlers in Skåne, one would have to re-write large parts of the country's pre-history. Third, carbon dating as we know it today was not invented until the fifties. Fourth, it was thought that the ice cap covered all of Norrland. Who would live there?
This has been a political hot potato, just as Kennewick Man, Spirit Cave and other caucasiods in North America are to the Native Americans. Land claims and fishing and hunting rights are at stake. This is no political joke. And so, it wasn't really until the 1990's that the scholarly community was ready to accept that the sami culture is at least as old as the one in Skåne, and as of this year, we have even further evidence of this with some astonishng new petroglyphs waaaay the hell up north. Even today, though, when you look at the new archaeological papers and research that's being done in Sweden and Norway, you'll find that the amount of research done on Götaland and Svealand is proportionally huge in comparison to that done on Norrland. The population down south is bigger, so spawns more scientists. To boot, the major universities, who sponsor the digs, were all located down in Uppsala or lower on the map, and up until the University of Umeå's archeo department started to really kick ass, there hasn't been much research done up north, Sami or no Sami.
The signs of a Sami culture being there much earlier than was originally thought, and of it being spread much farther south than had ever been expected, are IMO, so overwhelming, that coupled with the new evidence of the last few years, the theory of "Swedes first" can pretty much be put to rest.