you can't make a profit like that. banks (and tether) make profit by miniting news tickets out of thin air, lending the newly minted tickets at a certain rate, once the credit is reimbursed they usually destroy the minted tickets and keep the profit.
That’s one approach to profit, called “fractional reserve”.
Typically, people who want a 1-1 backed coin are uncomfortable with that model… so you instead take profit on the issuance: you charge $1.05 to issue $1 in tokens (while keeping $1 in the vault) — a process called seigniorage.
