He did liberate his slaves, eventually. And one of the last things he did before he died was to formally petition Congress to abandon slavery.
I don't think you really have any basis for that analysis of franklins psychology. If anything, I think the safe assumption is just that for most of his life slavery was there and people don't always question every part of society.
Brother, no he did not liberate a single one of his own slaves. Some escaped and he did not pursue, but his final slave died under Benjamin Franklin's enslavement 9 years before Franklin himself died.
Them facts you were looking for: https://share.google/J4zlTt102nc81Fhay
I think it's a sound analysis, he was a thoughtful and philosophical man who considered the nature of slavery heavily, and he benefitted from it greatly, and dearly understood its terrible nature, and continued it's cruelty, and freed no one.