Found a way for screen time not working for Discord problem
I was not able to set time limit for Discord on my kid's phone. And I searched the internet and here for an answer but could not. But I think I did find a way. Now with ios 17.4, there's Live Activities feature. I turned off In-App Content under App Store and turned off Live activities under Discord on my kid's phone. And discord became unavailable.
Hopefully kids don't find this posting.. 😅
iPhone 4s, iOS 9