There's no clear explanation for why some countries are rich and prosperous and free while others are not. Anyone claiming to have such a theory is bloviating.
Futher, you assume that the default is democracy and prosperity and we must explain why some countries lack that. But that's not the default! The default is corruption, privation, and instability. Those were certainly the conditions preceeding colonialism. The real question is how to escape that, and we have no particularly good theories there either.
Finally, the idea that certain countries have no agency is insulting and unhelpful.
But it seems like you're completely absolving these countries and peoples of all responsibility for their country and themselves, that in and of itself seems like the Western elites' "these people can't help themselves" approach.
The reality is likely a mix somewhere between the two, variable for each country and circumstance.
It doesn’t matter how great a nation you have, if US comes along and decides to put in place a dictator to secure low oil prices.
If US invaded Norway tomorrow and put a corrupt religious fundamentalist in power, there is absolutely no way you could blame it on the country, the religion or the color of the skin of he people living there.
As an Iraqi I am tired of people absolving us of agency as if the US just walks in and installs rulers left and right. There was no let there be Saddam, there were a lot of power grabs, internal struggle, and consolidation that happens before someone like Saddam becomes Saddam, and the most a western power can do is provide funds or international legitimacy