Yep, it’s a shame. I use the family settings for both of my kids and the system works well for the most part. I have found that somehow the google apps ignore downtime. I had to block YouTube entirely to shut it down, but it’s just an on off thing in the family settings.

It was a little weird to set up, it’s by account so you have to set up a unique Apple ID for yourself and an additional account for each person, then set up the “Family”

I logged into my ICloud account on a browser and I can see my family members but I can’t access any settings

I just checked again, there is no mention of access to screen time or family settings any way other than through the settings on an apple device. It looks like there are a few sketchy looking apps that claim to provide cross platform support for screen time settings but I think the only way they could do it would compromise your account by giving them access.

Sorry, I don’t think there is any way to manage parental controls without another Apple device. It’s all baked into the OS, the family settings are all in settings. I wonder if there is a way to do it online through ICloud but I doubt it.