Serious question, why would a widened ejection port effect accuracy? Winchester, savage Remington all have wider ejection ports still. Plenty of customs built off those?
The general consensus is the smaller the port,the more rigid the action will be. Making it less susceptible to torque and bedding problems. Promoting accuracy / consistency. You can in fact tweak the chit out of a M700 action with the action screws. The same apples to the blind magazine stocks as well.