It isn't like boats were invented in Scandinavia by the vikings. At Tanum, close to the present Norwegian border we have rock carvings dating back to 1700BCE, with prominent ships depicted. Boatrs have been important in Scandinavia for a long time.
https://www.tanumworldheritage.se/rock-carving-facts/?lang=e...
I know it's frustrating but media sort of reflects the most cautious and the most adventurous opinions of archaeology. Because saying vikings started at 793 is just a safe archaeological opinion, while even the romans built coastal forts along the british east coast to defend against "pirates".
Then the media will turn around and print something absolutely outlandish based on a total hypothesis, just because it attracts clicks.
Well yeah, there definitely was the period and cultural phenomenon called the Nordic Bronze Age, which also seems to closely match the dating of those rock carvings. You can read more about it elsewhere, but we're talking about relative largesse, reach and cultural interaction easily matching or exceeding that of the Vikings, originating and spanning a large part of the Indo-European sphere of dominance from Scandinavia to Mycenaean Greece and even beyond. Making and accumulating bronze itself drove the development of trade networks and connections of pretty extreme reach and complexity, unmatched for a long time after the Bronze Age Collapse.
Indeed - though the article doesn't really state the boats weren't in existence before the Vikings, it's about ship burials which apparently weren't supposed to exist in Scandinavia until the practice was imported from England. A theory I'd never heard before, but I guess that's on me. In any case, the find in the article seems to contradict that theory.
As for boats, the Viking age has been connected with acquiring sail technology, not so much with boats as such (which have existed for a long time, the rock carvings you linked to show depictions of boat designs which have actually been found in archeological digs, and that indicates that older, different carvings are also true and that boats were used for long distance trade and expeditions a millenium or two, at least, before the Vikings).
If the appearance of efficient sail technology really coincided with the beginning of Viking raids is still in the open I believe.