That is correct. The pedantic and accurate term would be "objective" since they are basically modify the win conditions of the round, but I chose to use the word "style" because it comes down to how you want to play the game.

There are many players that play "cs_" maps where you're technically supposed to be grabbing hostages and returning them to the spawn zone, but many players chose to play those maps in a different style where they just eliminate all the other players or run out the timer.

Likewise on "de_" maps you're supposed to plant the bomb, but instead many players choose to simply use the bomb to pressure (by essentially tricking the enemy into thinking you care about the bomb) people into situations and trade out kills.