That is false, and anyone who wants to understand the actual policy will have to read the article -- the submitter's title is wrong.
Google suggests and recommends an opt-in / opt-out dialog, but it's optional.
From the linked document:
> You must make it easy for users to understand what ads will be shown in your app, where they will be shown, and what the associated behaviors are, if any.
> Further, you should ask for user consent and provide options for managing ads or opt-out.
So the first one is a hard requirement ("you must"), but it doesn't really explain what's acceptable to meet it. Is the second one an optional requirement, because it uses the wording "you should"? In addition, the same requirement is mentioned again in a set of "guidelines". The whole section is really unclear to me.
(I am also not a lawyer.) Certainly. Violating a requirement might result in your app being expelled from the Play Store. Violating a guideline might result in a warning or a a strongly worded message to clean it up.
> You must make it easy for users to understand what ads will be shown in your app, where they will be shown, and what the associated behaviors are, if any.
Yes, but this doesn't require an opt-in dialog as the title suggests. The opt-in reference is a guideline.
> Further, you should ask for user consent and provide options for managing ads or opt-out.
There's that word "should", as in "people should avoid walking on the grass."
> So the first one is a hard requirement ("you must"), but it doesn't really explain what's acceptable to meet it.
You've raised an interesting point, one that lawyers are at pains to express if they can. A requirement that's ambiguous loses its authority. A requirement must be unambiguous in its meaning.
> The whole section is really unclear to me.
Yes, in which case it can't really be described as a requirement. These are suggestions, guidelines, not strict rules.
Why mention this opt-in dialog at all if it's optional? I can't think of an instance where a developer would choose to implement this voluntarily.
But you might ask why mention anything that isn't required. I suspect that Google is trying to get voluntary compliance for behaviors it can't require. The reason it can't require them might be that there are practices that violate the guidelines in Google's own advertisement activities. I don't know this for a fact, but it might be a reason to be less than demanding toward the Google Play app submitters.
For me, this is academic -- I have a number of Android apps at the Google Play store, but they're free and they don't show ads. Which means everybody else hates me. :)
Of course, it's up to Google be be clear with exactly what should or must be done. Unless they want to be unclear..
This kind of language exists in multiple other places in the Android docs for things that are more clearly suggestions. There's not enough consistency, plain and simple, but in the absence of clear "this is a requirement to be in the Play store" language, I absolutely, 100% interpret this as a guideline.
These are "should" and "should not" things, and things which you obviously must do to meet the guidelines are mentioned. To be clear about ads, you must be clear about ads, and you should be clear about ads.
Besides, they can already pull your app for basically any reason. This is just additional buffer, and it's something very few apps do, which includes e.g. Youtube which includes no such EULA when you launch it, no "opt in", it just shows ads on videos when they deem it valuable.
If they don't say it's mandatory, then it's optional. A mild form of the so-called totalitarian principle, which says "everything not forbidden is compulsory".