Not over night, but there is long term risk.

First, I admit, I believe in certain stereotypes that X people are more hardworking than Y people. (On average)

I believe so, because I believe that upbringing has tremendous impact of how an adult lives, commits and achieves things, and different cultures have different styles of life, and consequently guide kids differently.

UBI most definitely would not change things over night, but it could (I mean that it’s probable) start the shift towards “couch patato” like end of culture spectrum.