In theory I like your idea, but there are so many "edge cases" that make it a challenging thing to implement, and something that could backfire if its too strict.
These are not hard and fast rules, more of a system. Our youngest plays video games much younger than our oldest kid, since we have video games in the house now and didn’t with your first. However, I still make sure my youngest is getting plenty of tactile/analog play in as the majority of time spent.
We are mindful of potential Pandora's boxes though. You can't ban everything unhealthy without causing long term issues. You strive though to only introduce things when they're developmentally ready to cope with it, even if that means restrictions on yourself as an adult.
You work to constantly provide good examples via your own life, compelling narratives, etc. of people who exemplify the virtues you want to instill. That's how you help shape (the best you can) the life of someone with an innate identity to, when necessary, "just say no", or simply be uninterested in and unswayed by things that don't conform to their value system.
They aren't stifled by rules and wrestling with temptation--not valuing YT Kids is just who they are.
This is key. You’re trying to build a base of good behaviors but it’s flexible because the world is full of complexity and having overly strict rules is impossible.