Anybody ever go through "The Ra Expeditions" by Thor Heyerdahl?

Guy organized building and crewing 2 reed boats sailing from West Africa to the Carribean and northern edge of South America, rough starting point of the Olmec culture.

The first attempt broke apart and sank, but was incredibly comfortable and fleixble, being based on the designs used on Lake Chad in central Africa. The 2nd one made it to Barbados after 57 days at sea.

So yeah, reed boats can cross oceans. Sometimes, at least.

He also went west from South America on a balsa raft to Easter Island (Kon Tiki) , and tried to see how far he'd go on his last expedition, Tigris, from the now vanished reed beds of old Mesopotamia.

Heyerdahl is very famous, but here is the advanced actual follow up:
Dr. Dominique Görlitz
Most is in German ... but you can use subtitles. He found a solution from anchient drawings to achive what Heyedahl could not do: To cross against the wind to come back from America. Side/ Stack LeeBoards. Next Mission will start 2025.
Here is what I know in English:

Thank you. This would not surprise me, it was not unknown for the grave boats of Native Americans to wash ashore on the West Coast of Ireland.

Gulf Stream. Although you can miss and end up in the Arctic without hitting land.

Further, when it comes to reed boats, there are plenty of locations suitable for building them in ancient times around Britain and Ireland. If such sailors were shipwrecked, and even if they only knew how to build reed boats, they could still have got "home".