Yup. No Winders. Could probably load whatever M$ is doing for embedded devices these days, but it wouldn’t be free to distribute, like the ones provided on the pine64 site are.
My Winderz (and Kubuntu capable) Acer netbook of a few years back has Atom in it, though it is the 32 bit version.
Winderz might need special memory management or other things that the Pine board does not have, though. Trying Windows 7, 64 bit might work — or it might end up in a grand choke.