Original ji,
If I recall the beginning of this discussion, the young man was explaining that his father was basically coming from a Punjabi angle and was not particularly interested in Sikh belief. It seemed he was rather viewing this union as scandalous because it violated his perception of traditional Punjabi relations (a Korean girl?! What?!), while the boy's mother was guided by a secular sort of philosophy as to what is proper or not. The young couple themselves, if I recall, were unsurprisingly mainly following their hearts and not particularly interested in 'religion'.
I may have counseled harshly mainly because I perceive a trend towards atheism in mainstream society in these times, and I feel these youngsters are perhaps inevitably (it's a global world now) getting swept up in this world view.
Young people would be forgiven for having a soured view of religion because there is so much ignorance, greed and abuse of 'religion' in these times, and little example of living, dynamic spirituality, but to abandon the Sikh Panth and instead lean on the 'wisdom' of non-believers is nevertheless a betrayal, I think, of the mighty Gurus. It is because of this that I said, in essence, "you want to walk away from the Gurus? Fine, but then go ahead and seek out the 'guides' of the world: Dear Abby, Dr. Phil, Joel Osteen or other advisors of the secular, mainstream world...Cheers"
For the record, I believe there is absolutely nothing wrong with a Punjabi Sikh dating a Korean girl, I think it's really nice, but to my mind, she MUST come under the banner of Sikhi if that is to flourish. I think the Reht Maryada says as much: no comment about race, but a clear admonition to marry only those who believe in the Naam of Waheguru.
Sat Sri Akaal