Aren't progressives supposed to be in favor of diversity of cultures? Whether they are or not, a hardcore work ethic is hardly what most Americans would consider to be a problem.
Have you not heard of the Protestant Work Ethic? and how Europeans complain that Americans work too much, and don't all have 6 weeks vacation?
Asians have been discriminated against, but instead of whining about it they got to work to become the best. Now they're being punished for not sitting around waiting for handouts.
Blacks, for all their problems, have the votes to change the system electorally. But while there have been some success, there are strong oppositions from the status quo, and their progress has been hampered by political apathy from within that resulted from push back that slowed or killed further progress.