"People were better at seafaring then we used to think" is the opposite of what Heyerdahl believed. He thought that people drifted to Polynesia by chance, like fishermen from South America who were blown out to sea.
it is clear that in the 13th century, Tahitians used sophisticated navigational skills to travel the 2,500-mile distance and settle the Hawaiian Islands. Archaeological and linguistic evidence shows that navigators from Tahiti’s neighbor islands the Marquesas had settled the islands even earlier. Skepticism over the validity of those navigational methods has long muddied the waters. A most notable naysayer was ethnologist Thor Heyerdahl whose 1947 Kon Tiki raft expedition advanced the drift idea that colonization occurred only as vessels simply traveled on the tides. But the 1976 voyage of the Hōkūleʻa—guided by Micronesian navigator Pius “Mau” Piailug—resolved the debate. Piailug demonstrated his profound skill for reading the night sky and the ocean swells and safely guided the massive ocean-going canoe from Hawaii to Tahiti . . .
But skeptics remained, the most famous—but by no means the only—was Thor Heyerdahl. Not only did he reject the voyaging tradition, but he rejected the West-to-East migration as well. Heyerdahl argued that the Pacific had been settled by accidental drift voyaging from the Americas. His argument was based largely on the wind and current patterns in the Pacific, which flow predominantly from East to West. Where the oral tradition posed Polynesians voyaging against the wind, Heyerdahl argued it was far more likely that American Indians drifted with the wind. He made his bias particularly clear by designing his Kon Tiki raft to be unsteerable.