Online Courses and QuickTime

I teach many courses online and the video format the most supported in online learning management systems is QuickTime. I have multiple QuickTime videos in my online courses, and now I am being told that I need to convert my videos out of QuickTime because Apple is no longer supporting QuickTime for Windows. That is hours and hours of work. Why is Apple no longer supporting the one video editor that is the most used by online educators?