  A major complication in the search for jet quenching in proton- or
deuteron-nucleus collision systems is the presence of physical effects which
influence the experimental determination of collision centrality in the
presence of a hard process. For example, in the proton color fluctuation
picture, protons with a large Bjorken-$x$ ($x \gtrsim 0.1$) parton interact
more weakly with the nucleons in the nucleus, leading to a smaller (larger)
than expected yield in large (small) activity events. A recent measurement by
PHENIX compared the yield of neutral pion and direct photon production in
$d$+Au collisions, under the argument that the photon yields correct for such
biases, and the difference between the two species is thus attributable to
final-state effects (i.e., jet quenching). The main finding suggests a
significant degree of jet quenching for hard processes in small systems. In
this paper, I argue that the particular photon and pion events selected by
PHENIX arise from proton configurations with significantly different
Bjorken-$x$ distributions, and thus are subject to different magnitudes of
modification in the color fluctuation model. Using the results of a previous
global analysis of RHIC and LHC data, I show that potentially all of the
pion-to-photon difference in PHENIX data can be described by a proton color
fluctuation picture at a quantitative level before any additional physics from
final-state effects is required. This finding reconciles the interpretation of
the PHENIX measurement with others at RHIC and LHC, which have found no
observable evidence for jet quenching in small systems.
