But if this assumption is right, and if you consider how much fashion has changed over the last 60 years, does this mean that we are so very different from our grandparents?

assumption 是名词，来自动词 assume（假设、假定），指"未经证实的想法或观点"。这个词由前缀 as-（表示"朝向"）和词根 sume（来自拉丁语 sumere，意为"拿取"）组成，字面意思是"拿取某个观点"，即"假设"。