Sorry but I think you're the one who doesn't understand. Or you're shilling for Vlad. A customer with a given amount of capital can buy far more stock on margi

Sorry but I think you're the one who doesn't understand. Or you're shilling for Vlad. A customer with a given amount of capital can buy far more stock on margin than on cash. Buying additional stock on the firm's dime puts the firm itself at risk and also increases deposit requirements. DTCC deposit requirements take margin into account but even if that were not the case RH bought more stock on margin than it would have in a cash-only restriction. When Robinhood clients trade on margin, Robinhood itself takes risk on the position. There is no guarantee that margined trades will be liquidated when they go beyond minimum maintenance. Markets have discontinuous jumps all the time. So you can get situations like what happened with Archegos, where banks lost billions on the margin leverage that they provided to the customer. T+2 isn't archaic, it was introduced a few years ago and even in T+2 many firms are unable to deliver shares on time. Vlad started to blame T+2 because his firm didn't have enough money to cover deposits, but (A) that could have been resolved by restricting margin to reduce GME buying power, and (B) hundreds of thousands of those shares failed to deliver on T+2 anyway.