I recently obtained a PS4 Pro which outputs up to 4K on supported games (of which there are very few currently). Even on the games that support >1080p but less than 4K, I notice an incredible difference in quality despite the 50" TV screen being 5 feet away. (Final Fantasy XV is very pretty on a Pro)
I do wonder if that could be mimicked by rendering at 4K and antialiasing down to 1080. After all, if we don't notice in live video which is naturally antialiased, it would follow that we wouldn't notice in antialiased games.
I believe that's usually called MSAA, Multi-Sampled AntiAliasing. It generally does work very well for making a pretty image but it's also a lot of samples that'll be redundant. That's why there's some things like CSAA, FXAA that try to only do it on places where there's higher contrast or on edges where it'll be most notable.
SuperSampling or downsampling (there might be some nuanced differences between the two). AFAIK, MSAA works at the render resolution and you can have it in addition to downsampling, although at a very poor ratio of computation to reward.
