In case David Peters decides to conveniently delete it
Basically, the argument that Piksi is not a pterosaur – other than David Peters twisting the holotype to have a curvature – is because the authors of the new paper were intellectually dishonest in regards to depictions of the radius.
However, the alternative, that it is a bird, is not optional either, considering the absence of bulbous ectepicondyles on most birds – the general tendency seems to be towards reduction in most taxa, and nigh absent in the fowl-like forms Piksi is considered to be – and, most importantly, that the holotype is blatantly compared and showed to be fairly close to Arambourgiania, an azhdarchid pterosaur.
Furthermore, twisting a holotype’s pic to form a curvature strikes me as intellectually dishonest – certainly far more so than the authors of the paper.
Bottom line: evidence so far points out that Piksi was a pterosaur, even if not an ornithocheirid.
EDIT: An identity as a pterosaurs seems indeed most likely according to Mickey Mortimer: