This isn't effective because Little Snitch only sees the domains so apps can just serve the trackers on the same domain as essential services making blocking impossible.
The only way to prevent malicious apps from affecting your privacy is to not install them or not give them network access.
I derive lots of value from Little Snitch on my Mac, so this approach is more effective than not having anything.
And yes, having the ability to deny any app network access on iOS would be great.
Yeah but it might be because you are part of a minority. Once/if this is built into the OS, the app builders will have a strong incentive to do things differently.
Can, but they don't, because app developers are just as lazy and don't waste time to hide their trackers
They don’t because there is no reason to currently. If this was added then they would have a reason to and do it.
YouTube used to be separate domains for ads and then it got merged together so that you can’t block the ads network wide without blocking YouTube videos.
That's YouTube. One of the unlaziest dev teams. Spiderman Solitaire isn't going to bother.
Yet.