... the lines of magnetic flux are vertical and are crossing the coil as it moves horizontaly through them, if the long side of the copper strap/ribbon is parallel to the flux lines it causes more eddy currents to occur in the metal.
Think of the magnetic field as a beam of light.
If the beam of light hits a broad surface you get a lot of eddy currents. If it hits a narrow one you get few.
Your wire has to be pretty much at right angles to the field lines one way. So if you imagine you've got a field "shining" onto the table in front of you, your wire might be lying, say, left-to-right and moving, say, front-to-back. So far so good.
But if your wire is a strap you still have a choice: Stand it on edge, or lay it flat.
If you stand it on edge the field "shines" on a very narrow cross-section. Very little eddy currents. If you lay it flat it "shines" on a broad surface. Lots of eddy currents. So when you wind with strip you line it up so the field goes along the broad surface rather then penetrating it - the "standing on edge" orientation in your table example.
Turning a given amount of round copper wire into a pipe makes the surface "seen" by the field broader. So you get more eddy current losses, while the amount of generation remains the same. But with that hollow in the middle you can pack less copper in your slots, so you get less current generated. Lower gen and higher losses at the same time - phoey! You have to cool it a LOT - and use stronger magnets or more of them - to make up for that.
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