There's a difference between "infinite percent better" (because it was non-existent before) and "some percent better."

The fitness use case is a red herring and a software problem. Instilling motivation in people to do things they know are good but don't want to isn't traditionally a money-maker. You're building a better shame-er: how's Peloton doing these days? https://finance.yahoo.com/quote/PTON/financials?p=PTON (and that is "fundamentally different"!)

The iPhone as initially released isn't the iPhone brand success we see today, looking back: that's the iPhone + iTunes + App Store.

Which explains why similarly featured hardware didn't experience iPhone success.

That combination was fundamentally different, because it allowed you to easily do the 3 things most people wanted to on their phones (browse the web, listen to music, get a specific app).

At the time, 2008, there was no competition for that.

It would be until ~2010 that Android even launched rough (very rough) parity: HTC Nexus One/Samsung Galaxy S + Google Music + Android Marketplace

Two. Years.

I’m gonna be honest, I just sincerely have no idea what you mean by “fundamentally different.”

Like, Peloton is an exercise bike. A cool one! A great brand and experience! But it’s an exercise bike.

And it’s somehow more “fundamentally different” than this device that is trying to materialize sci fi?

I guess I just don’t get it

I'd say Peloton is as fundamentally different... as you can get within the fitness category. Absolutely agreed: its an exercise bike with adjustable resistance and integrated, network-connected stats. In objective terms, not fundamentally different.

But if even it's having trouble financially, fitness isn't a great category to win with technology. Branding and advertising, absolutely! (Nike?) But not tech.

Beat saber is not fundamentally different from DDR. I love both.

But that "some percent better" has a tipping point. MP3 players and Camera's in a mobile phone only matter to most when the capacity, quality, and battery life were good enough. Once they were, they were everywhere, and that was revolutionary. (The iPhone as such was just a better version)

The Apple Vision Pro is an impressive improvement. But I'm skeptical its at that tipping point. Making the tech work in a pair of regularly sized glasses, that don't need plugged in or a heavy battery, yet has similar functionality, would push it much closer to reality. No regular person is strapping one of these on to interact with the world as is. IMHO its current stage is: a very impressive toy. Which is totally fine -- with what's at stake and Apple's market position and cash, it makes total sense to try and be the leader here, until it materializes into the next thing or fizzles out. Either position is likely acceptable to Apple.