Negotiating power seems slightly tangential to the main issue, I don't think that take-it-or-leave-it negotiating tactics are inherently bad. When you buy food from the supermarket, you either pay the price they are charging or you leave - there's no negotiation.

But in that scenario, you can always walk out and walk into a competing grocery store and try to find a better price. The fact that you can walk is what makes it a competitive scenario, and not an anti-trust one. The question here is, is being able to walk away and use an Android (or other smartphone) product an equivalent (thus fair competition) - or is software in the iOS ecosystem unique enough that not being allowed to participate unless you follow arcane rules is unfair abuse of a monopoly.