“Your example has literally changed the lives of thousands of ordinary normal people,” a Reddit user named reality_czech wrote this week to Mr. Gill. “Seriously thank you.”Larry Tabb, the head of market structure research at Bloomberg Intelligence, said the rise of traders like Mr. Gill “would have been impossible even a few years ago” because every trade came with a fee and there was less focus on the markets on social media. But with people now stuck at home in the pandemic with easy access to free trading at online brokerages, “these guys saw an opportunity and they …
