Yeah but see that isn't true at all. I would actually challenge you to find me a tv smaller than 27 inches that DOESN'T have at least component out. Or at least a tv of a quality worth buying (vizio, lg ect...) S-video is a thing of the past to be sure, but composite, commonly used for video cameras and what have you and component, which believe it or not is still the "standard" for many cable/sat providers are here to stay, at least for the time being.
Now 5-10 years from now you'll probably be correct, but not right now.
In regards to multiple retro consoles I'm not sure what the point of that argument was. This is a Wii 2 hdmi converter, not a anything to hdmi converter. Generic hdmi converters can cost upwards of 100 dollars... the wii is special because it has digital out already. Regardless even a high end tv back in the day only had 3 or 4 sets of inputs..... you still had that problem back in the day. Just like hdmi does today. So cable/sat... that's one. Bluray player/media player that's two and you might have two more left if you are luckly. So that's one for a Nintendo console and one for a sony/Microsoft one. It makes more sense to use the analog inputs than to waste one on the Wii.