  We analyze the behavior of (net-)proton number cumulants in central
collisions of heavy ions across a broad collision energy range by utilizing
hydrodynamic simulations. The calculations incorporate essential non-critical
contributions to proton fluctuations such as repulsive baryonic core and exact
baryon number conservation. The experimental data are consistent with
non-critical physics at collision energies $\sqrt{s_{\rm NN}} \geq 20$ GeV. The
data from STAR and HADES Collaborations at lower collision energies indicate an
excess of (multi-)proton correlations over the non-critical reference. This
observation is discussed in the context of different mechanisms, including the
possibility of a critical point in the baryon-rich region of the QCD phase
diagram.
