You are basically tied to the lowest common denominator if running anything in real time.
Easiest way of sorting this out is to have as few states that need trasfer as possible. This is pretty straight forward with RTS type games, even FPS if you're clever. The more changes that you have to pass to the server, well, do the maths. It's why games like Battlefield, even with a relatively straight forward set of variables (direction faced, posed, load out, time that weapon was fired, bullet path/velocity, etc, etc) doesn't run more than 64 players - IIRC - in a map, and even then it took 2 years post-release for Dice to get a good tick rate. And Dice are an established studio who have done games like that before.
It's possible that a new company can come up with something revolutionary, for sure, NMS has that possibility - approaching universe generation in a new way with their proc gen allowing for a small team to make a lot of content. The jury is still out, obviously. ANd then you have Rockstar who have polished the behemoth that is GTA to a mirror-like shine. CIG, though, firstly are a new company without a track record of using or building their tools, but also nothing that they are doing is that revolutionary. All of their gameplay components have been done before. Their scope is huge, maybe, but what is actually new? Space fight? Done. PU? Done. Trading? Done. I dunno... what I've seen of SC is a bit like GTA in space, but GTA already exists.
