I think the purpose of a console is to provide a complete package. Controller, hardware capabilities, the gaming philosophy of the company behind it, the talent of the first-party devs, the UI, etc all play a role.
If you're only concerned with the guts of the hardware itself, I agree that console exclusives are silly and don't make sense. Despite the power differences, Xbox One and PS4 are more alike than they are different when it comes to the "guts". Same manufacturer. Similar processors and architecture.
But it's the support of the console that matters, too. PS4 isn't just a 7-core, 8 GB RAM box that plugs into my TV. It's a system where Sony curated indie developers from around to world to make content on. It's the place where Sony's top games are delivered. It's a system with a camera and a controller (with a lightbar and touch-pad), and it's gonna have VR soon, too. It's a system where the UI was designed to sleep and quickly return you to your game, and to play certain apps without having to completely exit your game.
This thread is chock-full of people making comparisons to phones/tablets as if that justifies annual console upgrades. Well, I'd like to make another comparison. People don't buy an Apple phone because it has the most powerful CPU and the snappiest UI (it doesn't). People buy an Apple phone because they like the package. They like how Apple emphasizes high-fidelity screens and innovative touch controls and makes their stuff easy to use. They like the suite of apps exclusive to the platform.
How is it so hard to see that people may buy a console package for the very same reasons?