So, is possible we have to go to UBI, at least temporarily
I'm kinda drawing the opposite conclusion from this sort of thing. If so many people are willing to just drop out of the labor force even in the absence of much support from government (since most forms of welfare are strictly limited in time, and not generally focused on young single men anyway), clearly the prospect of being "exploited" by an unscrupulous employer is not nearly as big of a problem as we used to think.
So what we need actually is to: (1) consolidate most forms of time-limited welfare into a single benefit that would work mostly like unemployment-insurance; (2) slash taxes on low-paid work (or equivalently, expand the EITC), as an efficient form of income redistribution that doesn't need anything like the sort of commitment from government that UBI does; (3) gradually deregulate the labor market, and stand ready to pivot to something more like a UBI if such deregulation does result in a deteriorated bargaining position for workers.
If the labor market keeps functioning smoothly, I don't think "social disruption of starving, angry and (some) violent, people" will be an issue. People, even starving people, will take up good jobs long before they resort to anger and violence!
I am thinking the first thing to do, is to completely remove income taxes on hourly workers. Would give an instant rise in velocity of money in the most local way, remove a burden from small business, and allow the IRS to focus on the larger corps, who are tending to offshore profits as well as people.
EITC seems like a good policy action, but as it is retro-active, it sure doesn't seem to put money in your pocket, it just keeps the Gov from taking more out.
As to unemployment funds, seems like if employers had to pick up employees half, but were allowed to...