Power loss recovery only works on PLA?

I think that in asking the question in the way that have, you have also answered it: it would only work if it doesn’t warp or detach from the printbed. Otherwise, it’s moot. I mean I suppose that rather than punting you might elect to accept an inferior print, assuming it’s possible to resume the print without it becoming a giant mess. Depending on what happened before and/or after resuming, it may or may not not be a good outcome, but regardless one could perhaps argue that providing you with that “hail Mary” option isn’t nothing.