I think you don't have enough experience yet to realize that, the more things change, the more they stay the same.
Yes, Redis wasn't available in 2010. But, you know what? Redis can't magically do something that code written in 2010 couldn't. You had to do a little more yourself, but given the primitives available in Erlang, not a lot more. And the solution in Erlang scales horizontally with adding more nodes, whereas Redis does not (Redis Cluster is a joke, technically speaking.) (Yes, you can do application-level sharding for particular use cases.)
If you have a specific kind of game that you want to build, with specific use cases and requirements that aren't met by existing technology, you may be on to something!
If you're just trying to "build a system," without any kind of strong evolutionary pressure on the features and implementation of that system, then experience (not just mine!) says you won't build something that's all that useful. The reason is that many billions of dollars, and tens of thousands of man years are spent on networked games every year, and the market will already have explored most implementation nooks and crannies for the kinds of games that have already been generally funded and delivered. It doesn't matter if it's games, financial trading, car maintenance or movie production -- if there's already a large market, and you don't really have a very specific use case that's not currently served by the market, then you're quite likely not going to make something successful.
Or to put it another way: Do things differently, is not particularly compelling and generally don't build successful projects. Do different things, is where it's possible to truly innovate and push the envelope of what's possible. And sometimes, you need to do things differently to be able to do the different things, but it's the different things that are the reason you win.
That being said, building systems is fun and educational. As long as you learn the right lessons, and draw the right conclusions, testing a bunch of things and pushing them until they break is always a good way of gaining more experience. After all, good choices come from experience, and experience comes from bad choices 😄