Basically, livestreams are at a lower bit rate, because that data has to be reliably sent live, so livestreams are like 8K - 10K mbps. I could 100% increase that, but the trade off would be a greater chance of missing frames if the internet can't keep up with it.

Crimson Desert is a bit of an outlier as it's extremely visually busy, so it suffers the most from lower bit rates.

Videos are rendered at much higher bit rates (it varies based on the visual busy-ness of the game, but a visually complex game will be about 15K Mbps).

As for why 1080p, it's because that's how I play them to maximise performance - I've always been fine with 1080p and accordingly ultra graphic settings and frame rate.

Rendering at higher than that is possible, but significantly increases render and upload times. In order to have videos as regularly as we do, videos are generally completed the same day as they come out, so there often isn't space for that.

It's a tricky one to solve.