Likewise, they knew that if it was left up the states, certain states like South Carolina would never ban slavery on their own, so they also amended the constitution and established that no person can own another person, regardless of what state they live in.
It is extremely unlikely that all 50 states will ban abortion on their own. Therefore, the only way to guarantee abortion is abolished in the United States is by a federal law. Otherwise, abortion will continue to be allowed in demand in certain states, just as they continued to allow slavery in certain areas when it was up to them.
Issues like owning another human being, or being allowed to kill an unborn child for any reason, are of such tantamount importance that they should be decided at the federal level, not at the state level. Human rights is not something individual states should decide.
You said that a trial by jury is mentioned in the 1st Amendment, but you’re mistaken. It’s in the 6th Amendment. I agree with you about slavery. Congress had the authority to abolish slavery, since it’s mentioned in the Constitution.