On platforms that are not limiting the sale of these stocks, people can sell, and then rebuy the dip, pushing their profits higher and higher with each transaction. In fact after your first round of profits, you can set aside your original investment, and keep pumping.

So you can actually "Keep buying" crush the hedge funds AND make a profit.

Especially when there is a short squeeze, which forces the hedge funds to buy more of the stock, that they are shorting, which pushes the price ever higher.