Athletes don't train to make the Olympics so their nation can take home the most medals, they're there as individual competitors. The Olympics aren't really presented as some large metagame, it's about the actual athletics.
It creates some interesting problems which vary between the different types of sport. Pre-games the programme is going to be set up so that all the athletes cooperate to make each other better and maximise the programme's chance of success, but the athletes are also internally motivated to minimise their opponents' chance of beating them at the games.
In my experience there's plenty of meta-game going on all the time! (Disclaimer - I'm not an Olympic athlete myself, I'm just close to the programme socially in a particular sport).