I don’t think this statistic should be that alarming. One of the main roles of the jail is to be the place where suspects are held pretrial. If convicts were taken to prison directly from the courthouse immediately after conviction, and if short term sentences were served in prison rather than jail, the percentage of unconvinced people in jail would have risen to 100% - and note that these are two technical changes that don’t worsen the incarceration problem.

And there is a problem. I’m not saying there isn’t. I’m just saying this number is not a good indicator of it.