Screen time not working for TikTok, YouTube, Snapchat, Roblox - Apple, please help!

I have screen time and app limits and restrictions on all of my children’s devices (ages 10, 14, & 17). They each have a iPhone and an iPad, and the older two have Apple Watches.

I set individualized downtime and app limits for each. (We agree on the limits.)

These apps and websites escape the limits (I’m sure there are more, but these are the biggest source of frustration for me because these are the apps that suck them in):

-TikTok (app & website will not be limited)

-YouTube (app will not be limited; some iterations of the website will work despite the main YouTube website being restricted)

-Snapchat (remains accessible 24/7 no matter what limits are set)

-Roblox (remains accessible 24/7 no matter what)

I will post separately, but deleting these apps also does not work because if you have family sharing turned on, any child can get the apps the other children have without asking permission and even if I have “no not allow” adding apps selected.

Numerous web searches and Apple Community searches do not provide solutions, only consensus around parent frustration. Apple, can you please ensure that apps are screen time compatible or not allow them to be used on devices where minors are logged in? If this is a multi-device problem, please identify a solution that addresses this and allows parents to help their kids draw their own limits and stick to them.