Another day, another Apple (NASDAQ:AAPL) iPhone 7 rumor.

The most recent speculation comes from Fast Company, and for the most part the "source with knowledge of the company's plans" is reiterating what the Apple rumor mill has already been saying for months. But let's go over it, just for good measure.

Stop me if you've heard this one before
The next iPhone is still expected to ditch the traditional 3.5 mm headphone jack, presumably in order to be the "thinnest and lightest" iPhone ever made (again). Audio functionality will be integrated into Apple's Lightning connector, which it has been working on for years (Apple introduced specifications for Lightning-based headphones in June 2014). Apple is reportedly working with its audio codec main flame Cirrus Logic (NASDAQ:CRUS) on a newer audio chip to facilitate audio over Lightning.

Waterproofing has been all the rage lately among competing smartphone OEMs, even though Apple quietly beefed up the water resistance of the iPhone 6s without really telling anyone about it. While it's a little peculiar for Apple to pass on the chance to brag about something, the most likely explanation is that it wants to save its breath for a major waterproof marketing push for the iPhone 7.

Wireless charging is also rumored to be in the cards.

Enough is enough
Here's the thing: consumers don't really need a thinner and lighter iPhone. The device is already as thin and light as it needs to be, yet Apple's endless pursuit leads to some very real sacrifices in functionality.

Specifically, a thinner and lighter iPhone likely requires a smaller battery, and battery technology isn't improving at a rate where increased density can offset reductions in size. However, Apple has been very good about optimizing the iPhone's energy consumption in order to maintain battery life. But one of the most popular requests among iPhone users is greater battery life, and Apple's surprise battery case that it launched last month seems to be implicit acknowledgment that perhaps the iPhone's battery sometimes needs to be supplemented.

If offered a choice between thinner and lighter or greater battery life, I'd bet most people would pick the latter.

Deja vu
On top of that, removing the standard 3.5 mm headphone jack is a pretty big ask, since users that have invested in a lot of audio gear will suddenly need adaptors or new peripherals. For instance, I have a nice pair of Bose QuietComfort headphones that wouldn't be usable with the iPhone 7, unless there is an adaptor. I don't really need more adaptors.

But all of this can also be said about Apple's initial transition to the Lightning connector in 2012. Doing so abandoned the entire ecosystem of 30-pin Dock connector accessories that third-party manufacturers had spent building up over a decade. In the years since, the complaints have subsided. It's also not unlike the MacBook's move to USB-C, which similarly integrates many functions into a single port and requires various adaptors for backwards compatibility.

Fast Company also suspects that Apple will no longer include a set of headphones with the iPhone, requiring users to separately purchase Lightning earphones or headphones, potentially sporting the Beats brand and juicing the accessories business (not like Apple needs to). Apple would also get some licensing revenue if third-party companies make MFi-certiifed Lightning headphones.

Apple has already said that it has no problem pushing people "beyond what's comfortable sometimes." Maybe users should expect to feel a little uncomfortable upgrading to the iPhone 7, but they'll probably still do it anyway.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.