“Ethics” ….
Pilgrimage to Santiago and the “ornate religious structures” belonged together, have the same roots, come from the same eras, had the same purposes (your salvation, your soul in the Christian meaning, being free of sin in the Christian meaning).
Those who appear to have concerns about the cathedrals and chapels because of their wider historic context and events - the bad things that happened, the progroms in Spain, the monarchs’ edict of 1492, the economic exploitation of the colonies, the missionary drive, evangelisation - do you have the same concerns about pilgrimage?
Pilgrimage did not happen and develop in a vacuum, in a context free space.
Or do you manage to separate walking today’s
Camino de Santiago from the darker aspects of a distant past but can’t do the same for today’s religious buildings? They, or their purpose, also changed: They are now open to all to visit, and one of their function today is that they are places to be visited and to be admired for their art and their architecture and no longer exclusively places to pray for Catholics.