Why are the dark energy and matter densities comparable today?

With $\rho_m \sim a^{-3}$ and a constant $\rho_\Lambda$, the ratio $r = \rho_\Lambda / \rho_m = (\Omega_\Lambda / \Omega_m) a^3$ is about 2.2 today and was about $2 \times 10^{-3}$ at $a = 0.1$. Find a mechanism (tracker or coupled dark energy, or anthropic selection with an explicitly defined measure) that predicts $r$ of order one at the epoch when observers form without tuning its parameters, while staying consistent with the measured $w(z)$.

A model that predicts r of order one at the observed epoch and makes a further prediction for w(z) or for dark-sector couplings that is later confirmed.