  Several studies in the literature have found a disagreement between data on
Baryon Acoustic Oscillations (BAO) derived using two distinct methodologies:
the two-dimensional (2D or angular) BAO, which extracts the BAO signal from the
angular two-point correlation function; and the three-dimensional (3D) BAO,
which also exploits the radial signal imprinted on the large-scale structure of
the universe. This discrepancy is worrisome, since many of the points contained
in these data sets are obtained from the same catalogs of tracers, so we would
expect them to be consistent. Since BAO measurements play a pivotal role in the
building of the inverse distance ladder, this mismatch impacts the discourse on
the Hubble tension and the theoretical solutions to the latter. So far, the
discrepancy between 2D and 3D BAO has been only pointed out in the context of
fitting analyses of cosmological models or parametrizations that involve a
concrete calibration of the comoving sound horizon at the baryon-drag epoch. In
this Letter, we avoid the use of any calibration and cosmological model,
assuming that the Etherington (a.k.a distance duality) relation holds. We use
state-of-the-art measurements in our analysis, and study how the results change
when the angular components of the 3D BAO data from BOSS/eBOSS are substituted
by the recent data from DESI Y1. We find the tension to exist at the level of
$\sim 2\sigma$ and $\sim 2.5\sigma$, respectively, when the SNIa of Pantheon+
are used, and at $\sim 4.6\sigma$ when they are replaced with those of DES Y5.
We then apply a calibrator-independent method to investigate the robustness of
the distance duality relation when analyzed not only with 3D BAO measurements,
but also with 2D BAO. We do not find any hint for a violation of the cosmic
distance duality relation in any of the considered data sets. [abridged]
