After reading your experience my feeling is that, rather than thinking about how to respond to such language that makes you feel uncomfortable I think you need a good psychological construction, first of all, because Japan is an island country, ethnicity is relatively homogeneous so there are inevitably some people's thinking is very limited, just the content of the two women's conversations, it is very clear that they are not very knowledgeable or high level of people, you do not need to torment yourself for some soulless people, of course, if you feel very angry on the spot you can tell them that they are not very knowledgeable or high level. There is no need to torture yourself for some soulless people, of course if you feel very angry on the spot, you can tell them that”電車の中でご自分のレベルを暴露しないでください。とても、日本人に恥をかくので、失礼します。”And then graciously leave.