I get your meaning but it doesn't have much weight without any evidence. Certainly Osama has lied, and is capable of lying. But we do not automatically question the stated motives of murderers and bombers without additional evidence. We do not second guess whether abortion clinic bombers are actually anti-abortion. We do not hypothesize what the real motives of the unabomber were, we take it on face value that he opposed the advance of industry and technology etc.

Similarly, we have no good cause to question Osama's stated motives. When an organization repeatedly makes clear their motives through public statements; when that organization undertakes combat operations at such great risk and cost that they employ suicide squads to carry them out and when those operations comport with their stated motives; and when their other activities also closely align with those statements why question those motives? The only reason is because someone has a political cause they wish to shore up by portraying a major political force like Al Qaeda as something it's not.

For what it's worth, Osama was right. The west has been a corrupting influence on the Arab and Muslim world, eroding traditional values such as misogyny, oppressive political and social institutions, stultifying economic systems, etc. For the most part I think this has been a good development, as I value individual liberty, education based on rationality and science, the spread of industrialization and broadbased wealth, etc. But such things are roadblocks to the creation of a new caliphate, or something much like it, in the Islamic world, which is the ultimate secondary goal of groups like Al Qaeda after they have managed to isolate the Islamic world from external influences.