Edit: It was the extruder. One of the belt gears sheared off, and there was enough friction between the pieces that it still worked at slower speed, even well enough for the calibration test prints I tried. I had spares that I printed ages ago and now it works.

I started getting this weird exterior wall defect that I haven’t seen before. Calibration testers come out clean though and it’s driving me insane.

Using orca slicer with an e3 switchwire trying to print parts for my other printer so I can rebuild this one into something not a switchwire.