App Time Limits - frustrated parent

I've seen enough articles online about how to switch on app time limits in iOS to know how to do it, and enough articles from people saying it's not working. I agree in that the reliability of it is absolute garbage. Does anyone have any more recent and actually useful insight into this issue. And to Apple, sort it out. It makes your devices unsuitable for kids if we can't moderate what they can see and for how long. You've dropped the ball on this one big time!