= Solution
The <baryon-to-photon ratio> is extremely small, of order $10^{-9}$. Thus even when the typical <photon> <energy> is below $I$, the high-<energy> tail of the <blackbody radiation> contains enough <photons> above the <ionization energy> to reionize almost every newly formed <hydrogen atom>. <Cosmological recombination> becomes effective only when this exponentially small tail is also small compared with the <baryon-to-photon ratio>. Consequently \b[recombination occurs at a <temperature> much lower than $I/k$], consistent with $kT\simeq0.03I$. The exact freeze-out history also depends on reaction rates and expansion; the equilibrium estimate explains the large suppression of the <temperature>.
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