Your analogy is quite poor, and thus your argument is weak: A laptop has the option to maintain performance at current levels, or change behaviors depending on power source. Consumers have no choice in this matter of iOS and iPhones.
Just because there is a reason behind something doesn't mean it's in the best interest of all consumers that purchase a product. If Apple was transparent in this practice, then, yes, this would be much ado about nothing. They weren't. They've tried to hide it. Worse, consumers don't have a -choice- when it comes to enabling/disabling.
This whole issue is very telling about the Apple community, and I'm personally refreshed/pleased at the "discomfort" this practice has caused. We shouldn't be "outraged" over anything (these are simply mobile devices), but we should speak out when a company does something that smells of dishonesty.
I think Apple is doing a good thing here by extending the life of people's devices that would otherwise be almost useless due to aging batteries (unavoidable), but I think they went about this the wrong way. Other devices (Android - Samsung/Sony/etc) have had user-controllable, power-management controls for years: screen display management, CPU performance, RAM loads, etc that can be enabled/disabled at will. iOS needs this. Leave it on by default once it needs to go into effect, but then give power users the option to disable if they so choose. Win-Win.
This is an opportunity for Apple to step up and create a better experience for customers; they usually respond well to such public issues. I expect this to get cleaned up in the next iteration of iOS. I have a 2013 rMBP, and it runs very, very well and gets acceptable battery life. Apple is clearly capable of making devices that last.