Tether is Tether Limited, which is incorporated in Hong Kong and operates under the umbrella of iFinex Inc. It's literally a company.
They have a shit-load of US dollars. What they do is create "tokens" on Ethereum, Tron, and other cryptocurrencies to represent US Dollars. Again, Tether is not a cryptocurrency. It's a company that uses cryptocurrencies to create vouchers for US dollars that can be moved around the world on the back of other cryptocurrencies as tokens.
When someone wants to convert 100,000,000 to Tether, they wire 100,000,000 to Tether Limited. Tether Limited then "mints" 100,000,000 USDT on a cryptocurrency blockchain like Ethereum or Tron. The person then receives 100,000,000 Tron or Ethereum USDT tokens that they can send to crypto exchanges. They'll then trade the Tether for Bitcoin or other cryptocurrencies.
What does Tether Limited do with the 100,000,000 in cash? They buy US Treasuries and get their interest on it. That's how they make money.
So without Tether. What would the price of bitcon be? Lower or higher? Cryptos in general, lower or higher?
Probably slightly lower, but not by much. People use Tether because they can move US Dollars around very fast and without a bank gumming things up and charging fees.
What specific mechanism would cause the price to go lower? As in why does the price go down without tether?