Because 10rd mag limits have been proven to prevent suicides...according to Bayer.
https://www.wlns.com/news/michigan/skubick-pro-gun-control-lobby-to-introduce-legislation-in-mi-senate/LANSING, Mich. (WLNS) – Look for the pro-gun control lobby to introduce new legislation this week aimed at reducing gun violence in schools. This comes, of course, in the wake of the four student deaths at Oxford High School last week.
The Senate GOP leader Mike Shirkey reportedly told Senator Rosemary Bayer (D-Oakland County) before COVID-19 struck that he would allow a committee hearing on gun control legislation.
If indeed there was such a pledge, it would be a break through for the gun control lobby.