Isn't it used to the figurative meaning ? One could also say "an agressive elegance" for instance, but it doesn't mean the elegance is going to attack you. Agressive style doesn't mean you're going to be mean nor attack people, just that you're going to let less things slide and, as you say, sometimes hard game can be okay, even recommended (not letting a solo forward pass past you, etc).
It's common language and the lexical field of agressive is not especially bad in sport, since it's not as literal as "being an agressive person". Commentators may say "agressive" because of the "agressive" style in the settings, how would you name it otherwise ? I found things like Fighting spirit/Tenacity/Pugnacity? Isn't that also related to acting martial?
But I get your point and your question makes sense: is aggressiveness admired/promoted in general? To me, no of course. Take the fighting sports, fighters are in general the most agressive on the tatami/cage but they are also the most aware of the importance of avoiding aggressiveness in real life. It shows that sport is a particular place obeying particular rules, it shouldn't be mixed up with the life outside the field.
Coming back to the statements the commentators say about recommending playing more aggressive with green/blue referees, I'm pretty sure they also recommend to be softer if you abuse with red/orange referees.
No offense, but why the wording is not changed like "you were lucky not received red cards despite your agressive tactic" or something?
Don't they?
