There's a comment at the end of the article that poses a good alternate explanation:

> Measurements that yield a value for H0 from the CMB amount to an average over the entire age of the universe, whereas the two other measurements described average over a relatively recent fraction of that age. Considering that high-z redshift surveys have given fairly solid indications that cosmic expansion is accelerating, and thus H0 should be increasing over time, the 5.3 sigma divergence between the two values could be a direct result of the different durations for each average.