It's all very problematic to me.
In the vast majority of real fights you start off defending. Then, if you are sufficiently skilled/lucky, you turn the defence into a controlled attack or opportunity for running away. There are very few situations (for regular people) in which starting a fight is a good idea - possible exception being to prevent an escalation of the danger (i.e the situation getting much worse and potentially unsurvivable).
Most of the scenarios suit the arts we learn - or is that the other way around?
In a controlled environment things are even more difficult. You are expected to attack even though it potentially puts you at a disadvantage (assuming relatively equal opponents - unequal opponents wouldn't be a sporting contest). Also, you are severely limited on technique. Take boxing. Both combatants will generally approach each other in a defensive posture, from which they will lash out probing strikes. A kind of fortress mentality. The sport is designed this way (perhaps for safety) and is quite different to the bare-knuckle fighting of a hundred or so years ago. Now imagine you are stepping into a boxing ring as a MA player and you are told you are allowed to use sweeps and ground attacks. The boxer will be at a distinct disadvantage, as every time he advances in range of your legs - but not his arms - he will be in danger of the sweep.
Not a perfect analogy but hopefully it illustrates my thinking on this.
So, some will argue that MMA is closer to an ideal as it allows a greater variety of applications. And yet it still severely limits what the contestants can do, in the interest of safety.
Our training is not so limited. However, when constrained by 'rules of the ring' it is perhaps not surprising that people fall back on simple punching and kicking a la Thai boxing.
Ultimately, if the other guy does nothing aggressive then there is no need for you to do anything aggressive. There is no fight, and that is by far the best outcome.