When you put it into percentage form it leads to a false conclusion being drawn by those that don't understand it's based off dice. They see only the % and think oh I can't miss, or I can't hit.
That is their own fault then. If a weather report says there is a 90% chance of rain, that still means that there is a 10% chance that it does not rain. So it not raining, is still a possibility.
Which means in this case the % is a lie.
It isn't a lie, that is how probability works.
Which means in this case the % is a lie.
In the case of % on actual dice I personally rolling with disadvantage rolled 3 20's, an 18, a 17, the rest of my 30 or so odd rolls were all with modifiers added under 12 by going with percentage I should of been able to pass those skill checks at least 50% of the time, I failed every single one. My dm can barely hit any party member including the ones who have an AC of 12, yet can hit my AC 18 cleric/fighter nearly every time. He is known for his horrible rolls in every game he plays, his wife on the other hand I have yet seen fail. She has repeatedly rolled natural 20's in a roll. A guy on youtube Will Weaton has literally the worst luck on rolling, the call it the Weaton Curse. So in placing a % when it comes to dice it leads to false belief, and false beliefs are a lie. Far simpler to show the AC of the creature.
I much prefer showing percentages, in fact, if it did not show percentages, I would manually convert it to percentages myself, because for anyone who thinks mathematically its easier to work with. Furthermore, if you open the combat log and hover over the action resolution, it displays the dice rolls there for you.