While that's true, many of those languages with more flexible word order, such as classical Greek and classical Latin, also have the passive voice. Classical Greek even has a third voice called the "middle voice".
You're right. Those languages have morphological passive voice conjugations for their verbs. That, combined with their flexible word order, offers expressivity.
I was just pointing out that English, due to its strict word order, is more reliant on the passive voice to change word order than less inflexibly-ordered languages.
To borrow from a sentence I used in an earlier comment, here's a fragment of Spanish.
"...sólo porque te impresionó un espectáculo de magia barato."
The equivalent English would be "...just because you were impressed by a cheap magic show."
The English sentence has to use the passive voice to put the verb "impress" at the beginning of that phrase, whereas you still use the active voice in Spanish, just with the word order putting the verb first.
I agree. The OVS order in that Spanish clause is unremarkable, though SOV is perhaps more common "un espectáculo de magia barato te impresionó". Up to the 19th century I think SVO or VOS would have been acceptable but now sound archaic: "un espectáculo de magia barato impresionóte", "impresionóte un espectáculo de magia barato", and as far as I know OSV and VSO are completely forbidden: "te un espectáculo de magía barato impresionó", "impresionó un espectáculo de magia barato te".
You can play tricks to come close to OSV and VSO for purposes of emphasis: "A vos un espectáculo de magia barato te impresionó", "Te impresionó un espectáculo de magia barato a vos," but the "te" is still obligatory. And you can do something similar in informal or poetic English: "Just because, you, a cheap magic show impressed you." But the passive offers more flexibility. I posted some other English examples yesterday in https://news.ycombinator.com/item?id=44493065.
But Spanish's inflectional structure is very much reduced from classical Latin, with a corresponding reduction in word-order flexibility. I think any of the six permutations discussed above would be perfectly valid in classical Latin, although my Latin is very weak indeed, so I wouldn't swear to it.
