If they had capital to begin with. If this is some individual hacker without much for means, swiping $100k of BTC in a potentially narrow window when a security vulnerability is in place is greater than $0 while trying to line up capital and shorts.

That's a lot easier to trace than BTC transactions though. And of course even there if the adversary is determined enough you'll get caught.

If you do it in "real" markets, you get the attention of the SEC or similar agencies in other countries. Crypto is completely unregulated in this regard.

There are literally millions of put/short orders placed against TSLA every day. I don't think they track the intentions of every single one.

No, but if someone managed to hack a bunch of Teslas and cause chaos, driving their stock down, you can bet law enforcement would be looking at shorting activity.

With Elon Musk normal shitposting you could away with one well placed message to (temporarily) tank the stock.

https://twitter.com/elonmusk/status/1256239815256797184

Bad hacks are announced fairly regularly. I highly doubt law enforcement investigates shorts everytime one happens.