Ideally, EVERY console would have perfect BC, even if it meant buying peripherals (IE a USB or proprietary port accessory that was a cart slot for NES/SNES/N64 games on GC/Wii/Wii U). Well, or if systems could be built to last centuries and you could easily get one produced for you whenever, but in both cases reality tends to be unfair, so I like to have BC within reason, and I do worry that Nintendo held back too much with Wii U to accommodate Wii.
Do wish there was at the very least FAR stronger, near perfect support for downloading older games digitally, but I guess that's hobbled by a killer combination of apathy (from consumers and from publishers) and older licenses/copyright issues that get in the way. Latter could be addressed I imagine if there were the right cases to loosen things up or outright allow older works within reason, but only better foresight can address the former, and given how often assets get thrown away I doubt the industry has much of that at all. Nevermind when companies go out of business, or worse yet seem to become recluses that want to do nothing with their IP like IREM.