We have over three decades of evidence in the console market that a game can’t be successful if it requires a non bundled accessory.

Guitar Hero [1] and Rock Band [2] were hugely successful [3] and required bigger and more expensive accessories than a simple gamepad.

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[1] https://en.wikipedia.org/wiki/Guitar_Hero

[2] https://en.wikipedia.org/wiki/Rock_Band

[3] Guitar Hero III was the first game to reach $1 billion in sales https://arstechnica.com/gaming/2009/01/guitar-hero-iii-first...

The iPad Pro doesn't come with a pen or a keyboard but that doesn't prevent them from flying off the shelves anyway.

How many successful apps require a pen or keyboard?

Microsoft Office and Google Drive would be the big ones. No one's paying $799 to watch Netflix when a $250 iPad will give them the exact same experience.

And notice that neither Microsoft, Google, nor Adobe sell “iPad apps”. They sell a subscription that allows you to use their apps across all platforms.

I've never paid for the app versions of Office or Drive and have used them for years. You can still use them across multiple platforms free of charge.