The purpose of pre-trial release is to let those out who are unlikely to cause harm or flee while they await trial.
1) If someone poses no risk, they are released.
2) If someone poses a risk, they are detained.
3) If someone poses a risk and is detained, bail is a tool to allow them out and ensure they return. Without it, you just keep them in jail.
Cash bail certainly provides advantages to those with assets or credit, but this is a separate issue.
This is where it breaks down. I don't think you need bail to make sure they come back.
Today those who are a low flight risk can put up collateral to make sure they come back
First, they should be asked if they believe the innocent person should be compensated for time and defense costs. Second, if they believe compensation is in order, they should be asked if they believe the prosecutor or the state should pay that bill.
A poor person who is finally acquitted after months of waiting in jail is likely to be released to homelessness, unemployment, and debt. They will also be suffering from the mental and physical trauma of their incarceration, which makes it more difficult for them to deal with their situation. Crime may be the only realistic means for them to survive, even if they have never committed a crime before.