"linked" doing all the legwork for "traditional folk myth" because linkage to an a-historical figure is at best, post-hoc reasoning over tales. This is like Ararat is linked to Noah's ark: non-probative linkage.

Hence the final sentence's use of "lore"

Interesting they previously dated it to medieval times. I guess there was insufficient structure to push back further and the most logical assignment in date and time would be early medieval because late medieval structure probably would have had more development around it. As I understand it quite a lot of early medieval structure has simply gone, as communities failed, moved, or land changed purpose. When people find things, if it's not a continued occupation building its foundation stones and detritus.

Before bio-archeology and radiocarbon dating all you had was prior knowledge and hunches. Probably it's been held to be medieval for a very long time in the archeology community, back into when it was antiquarians.