Test-optional means a school will review your application without SAT or ACT scores. It does not mean scores are ignored when submitted, and some schools have returned to requiring them.
Send or withhold
Compare your score to the school's middle 50% range. At or above the midpoint, send. Below the 25th percentile, withhold. In between, consider how strong the rest of the file is.
Where scores still matter
Merit scholarships, honors colleges and some majors often use scores even when admission does not. Check each program separately.