But therein lies the problem. Games like StarCraft have certain build orders that greatly increase your chance of victory no matter what the other player does. At that point it isn't strategy, tactics, or even decision-making anymore; it is just rote memorization and regurgitation of established "battle doctrine". So you are no longer winning because of your own abilities or skill, but because you just copied the methods developed by others.
A true RTT or RTS game would create an environment where no one tactic or strategy would prevail all the time, or even prevail on a consistent basis. It should force players to constantly have to adapt and change how they play instead of allowing them to develop one or two "ace-in-the-hole" tactics/strategies and just repeat it over and over again.
Doesn't real life have ace-in-the-hole tactics/strategies as well though? Like, just nuke them. How do you counter that? Nukes.
I think certain modern board games get the closest to this idea of many strategies being equally viable.
This article says a lot about how strategy developed:
http://www.scholastic.com/teachers/article/strategy-and-tactics-military
I like Nathan Bedford Forrest's quote:
Get there first with the most men.
The key way to make various strategies possibly good is to randomize some feature of the game, which gives bonuses to certain strategies. Starcraft developers were certainly aware of the effects of the map on gameplay. In SC2, maps generally all have choke points, to stop zerg from being overwhelming. They generally don't have protected cliff-islands, to stop tank drops from being overpowered. In SC1, only specific maps were played competitively, because maps that didn't conform to this recipe were too one-sided for certain races.
Random map-making fixes some qualities of this. If you don't know the map ahead of time, it's tricky to figure out the best strategy. Air units, scouting, and fast units gain more priority. But this could be countered by a rush, if someone figures out where you are and troop travel time is somewhat low. In civ, the number of cities you might build is highly dependent on terrain (and luxuries). The number of cities you build has a huge effect on your overall strategy, generally.
Board games like Terra Mystica give random benefits based on turn number, such as if you are at turn X, and you have this thing, you get an additional benefit. This sometimes makes sub-optimal strategies into optimal strategies. Strategies have to be planned around the random benefits, which are viewable at the beginning of the game. This helps make sure people don't always do the same thing, because if the random features don't favor the strategy, it won't be as effective.
Another fun board game I played has a feature where you choose 5 actions for each turn from a set of about 18. These actions are represented as cards. The cards have multiple effects, but if someone else uses the same card as you, both of you share the results of the action, rather than someone getting double benefit. Thus, it becomes more effective to do a unique strategy, because your cards will be more powerful. There's more to it than this, but overall it rewards having a unique strategy and predicting your opponents strategy to sabotage theirs.
So randomization is done either via other player actions or via game features at the beginning of the game, or both. Perhaps a civ-style randomization for Civ 5 could be to change which techs lead to what, or to change costs of techs, or to change effects of buildings, or effects of policies,etc. However, based on the large amount of turns in civ, the snowballing effect of a civ with a superior early game will offset the entire outcome of the game.
Terra Mystica and other board games fix the snowball effect by making various actions throughout the game gain you "points." You can sacrifice economy for points for much of the game, have a terrible state at the end, but win based on points. Starcraft and Civ both suffer from having the result of the game be dependent on economy, rather than incremental victories, necessitating having a strategy which attains a better economy than opponents. (There are other intricacies at play, but this is the largest factor.)
Mobas like LoL heavily suffer from the snowball effect as well. However, the snowball effect is
fun for the person doing the snowballing. I don't think people really enjoy a game that strive for perfect fairness. Otherwise, games like Chess or Go would be more popular.