花街老中 came to US mostly in 1982-1990, who had pursued PhD in math/physics but didn't switch to CS or EE. Hence, many couldn't get out of school and find a decent job before getting a GC via "5/35". From 1993, however, they gradually found quant jobs at various WS firms with their hard skills in math. By the time the great WS expansion of 1998-2007 started, most of them had had solid positions already. Therefore, the WS contraction since 2007 has not hurt them much.
花街小中, OTOH, got attrcted to WS only after the late part of the 1998-2007 expansion, most of them with just some soft-skill degrees such as ECON/FE/IB. They served as "analysts" with a 2-yr "Up or Out" contract. Thus, it is no surprise they have suffered most since 2007.
When will the next WS expansion start again? "Only a fool predicts, and greater fools listen." But the history shows that one had to wait a good 30+ yr period to see the next expansion after its 1957-1966 expansion ended.