This no-true-Scotsman fallacy is typical of how leftoids frame their struggle, but no. The whole thing was rich kids all the way back to Marx and Engels.
The rank and file of Marxist movements back in the day up until the mid to late 20th century were almost always actual factory workers or peasants (in China primarily). Once the working class in the US was gutted by immigration and offshoring, there was a big shift to the point where the scions of the incredibly wealth, ever-shrinking group people who own an every expanding share of productive enterprises, populated the leading roles, and the foot soldiers became drug addicts, the unemployed, sexual deviants, and all other manner of societal dross.
It's just historically illiterate to claim that this was the case in the early 1900s - unions back then held a lot of power, and unions were populated by factory workers, tied to mob power, and often operated at the margins of the law and were absolutely opposed to the owners and were led by people who came up through their own ranks. If you've ever operated in the circles of the very wealthy into this country, and talked to their college-age/adult children, and ask them what they want to do, they often airily say something like 'activism' or 'work for an NGO'. This is what they're referring to: turning any protest movement into a moral laundering program for people like them, turning it to serve the financial interests of their families, and sabotaging any attempt to point criticism where it belongs - at people like them. That
is a unique development. If you think that insisting that these scum should be allowed to take the mantle of labor movements who are still looked upon fondly by a lot of people in this country is a win, well then I'd just say that you don't understand long-time strategy. 'Our movement gave you weekends, higher wages, and sick leave' is the fig leaf they hide behind. The winning move is to tear it off.