You can push every match, win most of them, and never be a 5.0 level player.
Or, you can learn to hit hard, then figure out how to get some IN, make 5.0 or better, and miss a bunch trying to beat a peer, knowing if you don't hit out, you'll give THEM a chance to hit their best shots against you.
But then, you're now playing 5.0 and better tennis.
In the pro player level, lots of guys can choose to hit softer and be more consistent....and get beat by a hard hitter. They have to balance their defense with some amount of offense.
YOU and I, being mostly 4.0, can get better by learning how to hit harder. We can win more matches right now by pushing also. Which is your preference?