That’s exactly how you do it. You need an “actual controversy” to have standing to sue, not just a theoretical one.

That is exactly how you start a lawsuit, because filing a claim in the US system requires “standing”. It’s perfect if the plaintiff can point to clear examples of this kind.

With Google: probably, as there isn't just one appstore.

I am not sure about Apple.

Depends on whether society thinks you’re doing it for a good cause. Laws should serve people. If “the people” think they’re unfair, they will allow lots of technically illegal actions to change them.

Mahatma Gandhi did that, and society nowadays thinks he was within his rights.

Uber also did that, but isn’t universally acclaimed for it (¿yet?)

(There’s a large legal difference in that the Gandhi was a person and Uber a company, but Uber somewhat got away with its actions. That’s an indicator that society isn’t unanimous in condemning those actions)

This could and, I think, will be similar. This strong protest by Epic will lead to change.

where did you get your law degree?