I agree, the story is pretty long winded, but they are not wrong: Vikings never referred to themselves as vikings, nor did anyone else at the time. The word is old Norse of course but as far as I know was not used by Snorri.
My understanding is that it was almost a derogatory term.
They are also correct in that modern usage of the word started with the national romantics of the 19:th century.
So the word itself is a (almost) modern invention or at least re-purposing. Does not matter. We need words for things.
Snorri Sturulson definitely used the word viking if, as most scholars hold, he was the author of Egil’s Saga. That text is replete with the term, and it isn’t used in a derogatory sense at all. It is an activity performed by the characters considered heroic. It’s even right there in the first paragraph:
“Úlfr hét maðr, sonr Bjálfa ok Hallberu, dóttur Úlfs ins óarga. Hon var systir Hallbjarnar hálftrǫlls í Hrafnistu, fǫður Ketils hængs. Úlfr var maðr svá mikill ok sterkr, at eigi váru hans jafningjar. En er hann var á unga aldri, lá hann í víkingu ok herjaði.”
Snorri uses it in several sagas (given time I might look it up, but not now).
In the christian middle ages it could be used as a translation for the word for pirat. So talking about "the age of the vikings" is really like talking about "the age of the pirats", where the people themselves are norse, danes or swedes etc.
It was simply the word for pirate. They described pirates in the Mediterranean as vikings, despite them not being of Norse ethnicity or culture in any way.
Yep, this kind of meaning seems to have been in use until quite recently at least.
The 1967 Movie "The Viking Queen" is about a fictitious eastern English queen during the time of Roman occuption. She's definitely not Norse, but the intended meaning of "Viking" here is "a raider or plunderer".
So the word itself is a (almost) modern invention or at least re-purposing. Does not matter. We need words for things.