That’s how polls work. I’m not sure if you genuinely don’t know, but that’s just how they are done.

You can very accurately extrapolate data on the entire population with just 1000 participants. The flaw is in geography distribution, population distribution, willingness to poll, and other types of sample bias, but if they account for those then that’s perfectly valid.

Anything last gen or older. Retro doesn’t mean ancient. I have everything from the Atari 2600 to the Wii U in my retro collection.