While archaeologists definitely do tend to underestimate the viability of sea voyages, don't consider 1491 a work of fact. It's rather fast and loose with its interpretation. Zheng He or members of some of his 7 voyages did get to the east coast of Africa, but any further movement is not supported by either evidence or literature.

You can check out https://en.wikipedia.org/wiki/Pre-Columbian_trans-oceanic_co... for some debunking.

Most places on earth, America included, are or were reachable in small watercraft at certain times of the year, even without sail, given certain weather conditions. Only the remotest islands truly required advanced seafaring for repeat navigation.

Anyway, aside from isolated boating incidents there are far more impressive stories that are buried by popular history and its political supporters - the use of Persian as a lingua franca for trade and diplomacy as far away as China, various Indian Kingdoms throughout Southeast Asia and up to the Chinese border, entire civilizations whose expanse was extremely significant but virtually nobody has heard of, successful cultural genocides on grand scales, etc.