It's probably a believe and rendering of communist, socialist that the Buddha "advocated for education to all humankind without considering...". We already know that outcome called "Khmer rouge", (Khmer, pali khema, "person or land at peace", epic for Arahat), to give one of many samples, by adding red to wise, desire/aversion to calm.
As he told, his teachings are just for those "ready to be tamed" and of course it is a strong religion (i.e. binding, robe to something), but without an idea of "re" like others may advertise with certain anchors for pride. One hasn't been bond to liberation before the path to master.
So if one calls it "ligion", such would be probably better.
Is Buddhism has more affinity towards a free-thinking society...
The Buddha did not much care about ordinary society but only for his Re-ligion, Legion, the Sangha. Although he was open for good individual advises, he had neither the idea to lead nor to feel responsible for what societies are doing or not.
He also taught on and on on how one should thinks, even on what, so it can not be said at all that the Sublime Buddha was a "(Pseudo-)liberalist" but one who gave strict advises on how to gain real liberality.
And he rebuked the Scientist very often and he taught of what one should incredible fear and what not.
Since it is a very black and white way out of Samsara, his Dhamma will probably not fit even a little to modern ideas. It's just that trades are good in selling new things people are not able yet to know it a original or a market-fake.
As for Buddhism, that is housholder-stuff... they love to build their own things and sand-castles.
(Note: this is not given for Buddh-ism, exchange, stacks, trade and gain binding to world and common societies but for liberation)