Tether will never reach $0, because if the price of Tether reaches $0, then it's means Tether is not safe anymore (scam), because Tether is a stable coin and is in the top 5 on coinmarketcap, so the price of Tether will always be stable and will not crash to $0, because Tether has a lot of support (high volume and market cap).
Tether will never fall like other altcoins and not fluctuate with the price on the market, tether will remain $1 and will never fall even though there have been panics before because traders did not validate the fake news issue so it fell below $1 but only temporarily, hopefully traders are wiser and do not repeat the same incident in the future.