When did all the short-term "traders" join the forum?
Looking at the trading across the days he sold, his portion of each day's share volume (93M, 99M, 128M) were not a significant part of them (average of 6.25% of shares traded across those days, right?).
It is perfectly natural to look for a simple answer to explain painful moments in time. That is how our brains are wired. But, the market is not ever going to be that simple. There are millions of variables at play on any given day. Any combination of which are the actual reason for the SP value at any given moment. Trying to blame this decline only on Elon's cashing in HIS shares for something he wants is foolish at best.