Right now the absolute calibration is done by matching nearby supernovae with Cepheids and then extrapolating to remote SNs which is where the cosmology lies (essentially).
Gaia gives better Cepheid distances, decreasing the total uncertainty somewhat. But the big story is the calibration of the intrinsics supernova brightness (and its variation), so while better Cepheids help, its mostly by further closing a already unlikely avenue of explanation.
The big crime of the article is portraying the field as thinking the tension is due to new physics, when in fact the difference between the CMB and SN determinations has been known for something like 20 years and for all that time been mostly viewed as something experimentalists get sorted. For a long time the values agreed within their stated uncertainties, and its only rather recently that they have pushed their statistical errors down enough that the difference can be said to be real. So its a while yet until the difference is truly trusted as something to be explained by new physics rather than some calibration error.
Gaia gives better Cepheid distances, decreasing the total uncertainty somewhat. But the big story is the calibration of the intrinsics supernova brightness (and its variation), so while better Cepheids help, its mostly by further closing a already unlikely avenue of explanation.
The big crime of the article is portraying the field as thinking the tension is due to new physics, when in fact the difference between the CMB and SN determinations has been known for something like 20 years and for all that time been mostly viewed as something experimentalists get sorted. For a long time the values agreed within their stated uncertainties, and its only rather recently that they have pushed their statistical errors down enough that the difference can be said to be real. So its a while yet until the difference is truly trusted as something to be explained by new physics rather than some calibration error.