If you're a hacker-type person who has already digitized your gamecube collection (or, let's be honest, downloaded the games illegally) then this doesn't matter. But for regular consumers, there needs to be a way to verify ownership.
Nintendo could have made some titles available digitally (which is what I wish they'd done), but that requires getting content rights sorted out for games that have never been sold digitally before, so the full catalog would not have been available. Also, there would have been a ton of hemming and hawing about "Nintendo is making me buy my Gamecube games again?!?" No comment on whether such complaints would have been reasonable.
Modding your Wii-U to run those roms?
I feel that probably qualifies someone to be regarded as a hacker -type
> If you're a hacker-type person who has already digitized your gamecube collection (or, let's be honest, downloaded the games illegally)
Either way, I disagree with your definition too.
The ”hacker-type” is the one figuring out how to mod the wii-u. The one following some instructions to perform it using provided tools is simply a end user.
Using a tool someone else built is definitely the gateway to hacker mindset and culture
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I have long had a total fantasy in this vein... what Nintendo could have done is release add-on hardware to read old media. Imagine a hybrid mini-disc and cartridge reader which connects to the Wii U via USB, and a Gameboy cartridge reader which connects to the 3DS via... uh, possibly NFC, Gameboy games are small and the games could be read once and cached to internal storage.
You could use this to add backwards compatibility all the way back to the NES and Gameboy! Games from consoles two generations back could have been run natively, everything older could have been trivially software emulated.
I don't think such a product would have substantially interfered with Virtual Console sales, it would have been too niche. Probably too niche to make sense in real life... but in my fantasy, the goal would have been PR. It would cement the idea that buying a Nintendo game is an investment which Nintendo will support long-term; whether a large number of people make use of that ability is irrelevant.