Do you think that minorities are "oppressed" in Western liberal democracies?

It depends on what you mean by "oppressed." If you mean systematically, that's up in the air. You can point to racism within justice systems, for example, but that's more of a problem of perception of judges than of the system as a whole. But if you talk about "oppressed" from a social standpoint, then there's little perspective that you can argue that oppression does not exist. This has been studied extensively; people in Western democracies, just like people everywhere, do have some degree of understated racism. One need only look at the recent US election, and the rhetoric directed at minorities (and at the ultimate racial breakdown of how people voted) to see this in action. The people saying that minorities aren't oppressed A), probably aren't a minority, and B) probably aren't overtly racist (although they could still be subconsciously so). Never forget that, in the US, segregation was the norm only 50 years ago and slavery was only 150 years ago. White supremacy has a long cultural and political history in this country, the effects of which weren't magically erased with the passage of the Civil Rights Act.