The max contract seems to create confusion. People see Lebron, Westbrook, Harden, Durant et al. getting the max and use that as the reference point when it's not. All those guys are worth far more than the max but can't get paid what they're worth.
If you look at the borderline guys Horford seems right in the mix. Carmelo, Conley, etc are better benchmarks.
And going down the list, if Alan Crabbe and Ryan Anderson are worth $18 million, is Horford overpaid at $26 million? I think not.