As I said, you don't understand the asset. You are not shorting Bitcoin as it is a currency. You may be able to short a trust fund holding bitcoin (GBTC) but you are not shorting the actual asset and therefore not affecting the world wide exchange prices.
You can also dabble in the futures market as one of the two exchanges is still active (CME). But, here again, you are not buying the actual currency. You are buying a promise through the exchange for a date and price locked into the future.
And, LOL, you say it is technically garbage yet a single bitcoin is now trading over $10,000 so it is obviously not garbage.
You can choose not to purchase, hold or trade it and given your limited understanding, that might be wise for you.
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