I've only been following it off and on, so have missed a lot about the evolution of the charges. Including this:
eu.jsonline.com/story/news/crime/2021/11/12/jury-instruction-may-clear-kyle-rittenhouse-gun-possession-charge-kenosha/8588970002/
Rittenhouse is charged with first-degree reckless homicide in the death of Joseph Rosenbaum. To prove that charge, the state has to show Rittenhouse acted with utter disregard for human life.
Prosecutors want the jury to find Rittenhouse guilty of second-degree reckless homicide if they found all the other elements of the crime except utter disregard for human life.
Schroeder declined that request, and will give the standard instruction for first-degree reckless homicide and one about self-defense. Rittenhouse maintains all eight shots he fired that night of Aug. 25, 2020 were in self-defense.
I remember a similar cascade of charges from the trial of the cop who killed George Floyd. It gives the jury the choice of finding someone guilty of a lesser charge, if they don't feel the first-degree charge is merited.
Of course there may be very good legal reasons why the judge refused to allow a second-degree homicide to be considered, but it created an "all or nothing" choice for the jury.