[Oyk]

Dumbfart sinkees parents used to send their children overseas to avoid studying mandarin...

That generation which didn't learn Mandarin or learn it well is now in their 60s and 70s. It does not mean they are less Han just because their Mandarin is poor. They speak English peppered with Hokkien, Malay and some Cantonese, Hainanese and Teochew, which is true Singlish.

China was backwards at that time so there was no point in learning Mandarin.

Different languages for different era. Now Mandarin is important but last time it was not 

Did these boomers lose anything? Nope