It has nothing to do with the shares being borrowed. That's a separate transaction that comes with a fee. The point is that the share is then sold. It's sold to someone who is taking the long position. The original owner of the share, from whom it was borrowed, makes their money in fees, and by investing any security deposit given by the borrower. They are not taking a long or short position.

Yes, that is how short-selling works, but you're claiming that the only reason the headline isn't "SPCX is the most purchased new stock" is for narrative reasons, which is patently false. Shorting necessitates that someone decides to sell a stock they do not own, which creates downward pressure on the price. Saying "there's always someone on the other end of the transaction" is true, but not at the same price. If what you were implying were true, the price of shares would never change. You probably understand this, but share prices decrease and increase due to the number of buyers and sellers. Hence, the more people that short-sell a stock, the lower the share price goes until it can find buyers.