When was the last time anyone overtly referenced the protestant work ethic except for the purposes of tearing down a straw man.
Many cultures, in the far east as well as Europe have similar "always be doing something productive" undertones.
I agree that the moralizing zealots that set the tone for early American culture were insufferable (and being so insufferable likely helped accelerate the settlement of the east coast states) but "muh protestant work ethic" isn't really unique to the US.