If you and I both agree to trade 0.000001BTC @ a price of $1,000,000/BTC, meaning the total value of our trade is $1, and we both know that the supply of bitcoin is 19,000,000 coins. Does that make the "Market cap" of bitcoin 1.9Quintillion dollars? Obviously not.
Market cap is a historically bad metric to track when comparing things like this.
So back to your question at hand, how would a $80B USDT market cap topple a $500B market cap. Well, first we realize based on the above silly example, $500B isn't necessarily the real value. If Bitfinex (tether) has been printing USDT and using that to buy bitcoin, then the market cap of BTC is inflated by an asset effectively worth $0.
Once this realization sets in, panic selling starts, and there is an overwhelming greater number of sellers than buyers, and it doesn't take $500B worth of trades to topple a coin with a $500B market cap (if that market cap is inflated by hopes and dreams).
If you and I both agree to trade 0.000001BTC @ a price of $1,000,000/BTC, meaning the total value of our trade is $1, and we both know that the supply of bitcoin is 19,000,000 coins. Does that make the "Market cap" of bitcoin 1.9Quintillion dollars? Obviously not.
Market cap is a historically bad metric to track when comparing things like this.
So back to your question at hand, how would a $80B USDT market cap topple a $500B market cap. Well, first we realize based on the above silly example, $500B isn't necessarily the real value. If Bitfinex (tether) has been printing USDT and using that to buy bitcoin, then the market cap of BTC is inflated by an asset effectively worth $0.
Once this realization sets in, panic selling starts, and there is an overwhelming greater number of sellers than buyers, and it doesn't take $500B worth of trades to topple a coin with a $500B market cap (if that market cap is inflated by hopes and dreams).