Yeah, the whole point of when you do/don't accept a call of "laces?" is to do whatever keeps the spotlight off you.
Neutral situation where no one will be upset by you stopping the restart for 10 seconds? You'll get more fuss if you deny the shout, so hold the restart and allow it.
Tense game where it comes as part of a pattern of the team trying to slow the game down? You'll wind up the entire opposition team if you allow it, so best just to keep things moving.
But if in the above situation, a defender has dropped to his knee, undone his laces and then shouts for you to delay the restart? Frustrating, but better to stop the restart and let him get back to his feet first. Throw in a clear warning to the player that you won't allow it again, but that's still less controversial than if the player lets a goal in with his laces undone or because he was delayed in getting back to his feet.
It's all risk-reward, and sometimes you're choosing the less-worse of two bad options.