What ways were Western nations hypocritical in

their treatment of their colonies?

The age of exploration fostered the ideology and policies practiced by Western European countries of extending their rules over foreign nations using violence and military intervention to gain political and economic control over the foreign nations' resources which became normal worldwide.

Western empires have usually pretended to advocate for democracy, freedom and/or equality but cynically contradicting themselves by depriving their colonized peoples from those, overthrowing their governments and setting up instead puppet leaders easily manipuated by the empire.

They basically pronounce rules for others but they do not have the intend to follow themselves.