There's really the types of people that are trading shares:

• Regular people like you and me. We have a brokerage account, we but a few companies we like, maybe we invest our 401k in some specific stocks. Typically this isn't a huge percentage part of the market, but it becomes bigger with well known stocks because that's what regular people tend to buy. This is "retail"
• People who invest for other people, mostly running mutual funds and ETFs. This is what most people's retirement money is invested in. Most of it is either index funds, or very close to the index, but it's a lot of money. I'd call this "funds" or "professional money"
• Big money that invests for itself, maybe they're trading for other people too, but they've got their own money on the line. This is typically some kind of hedge fund, and they're invested in all kinds of stuff.

When we look at the market what we typically see is the first two groups buying stocks. The hedge funds are often more concentrated, out just investing in stuff we can't, and overall shorting isn't typically a big part of most strategies.

With Tesla we're probably seeing much higher percentage of trades done by retail investors and hedge funds than you'd see in a typical stock this size. And we're seeing wayyy more shorting, like ten times as much.