requiring opting out is a huge barrier as shown in behavioural economics and definitely makes it "not easy" especially if no one else is seen to be doing it
One is by legible criteria: how long does it take & such.
The other way is: how likely people are to do it. That's how a UI design would be measured. How many more people sign up if I remove the "age" field from a form. How many fewer people become organ donate if you need to register online vs tick (or untick) a box on your lisence form?
The first way is how a regulator or judge would see it. The second is often the one that matters to how things develop practically. Eg how gdpr-ish consent actually affects realities of user control over their data.
A common pattern is to concede the first, and rely on the second to make it irrelevant. Opt out is available, but the "UI" design ensures that it's rare.