Are we seriously going to argue this? It's a competition if people make it a competition. Countries like China and the US very obviously compete when it comes to medals and medal count. Anything can be turned into a competition if you have more than one willing to participate.
There wouldn't even be a "medal tally" if some people didn't think this was a competition. There would be no point for the medal tally, listing countries as 1st or 2nd.