Ah, the Rollplayer has been met with its natural enemy, In Character Conversation, and proceeds to utilize its natural defense, the attempt to roll for diplomacy. Let's watch to see how the Game Master responds to this ploy to deflect from needing to explain their actions...

I wonder if Cory is impressed yet?

Something I just realized from reading Aangvanced: Luffy's Gears might be Luke figuring out how to use a D-Infinity

Honest question, what's a D-Infinity?

A sphere.

You mean that one from Gravity Falls?

Yeah, that's exactly where I stole the idea from.

A die with infinite sides. There's a flashback in aangvanced where a guy whose name started with an M, his character is Deku from My Hero Academia, has made his fists do 2dInfinity+58 damage.

That 58 is probably wrong and also irrelevant but I don't feel like looking up the specifics right now, nor am I certain of the guy's name but I'm pretty sure it started with an M.

His name is Micah and he does 2dInfinity+59 damage. And can do 10 of those attacks at once. So the moral of the story is stay far far away from him.

Ah, so close.

Many times, people will fall back on their numbers as opposed to using words to solve a conflict in rpgs. It does seem odd that they would trust an arbitrary roll of the dice over trying to organically argue their point, or at least convincingly bluff.

Story time: Share a time when someone has said "I haggle" or "I use diplomacy" to solve a problem.

It's for the exact same reason we don't ask the barbarian's player to lift a truck himself or the wizard player to conjure up his own demons. Nobody is capable of everythng their character does so skill checks allow us to simulate making the perfect argument.

And the reasons not to do it are the same as why you don't just roll for auto fight or making battle/heist/whatever plans because your character would be better at it than you. Yeah there is a limit to your verbal skills so you can't properly portray a master diplomat without some hand waving. You could go for descriptions+rolls instead for instance but just rolls removes one of the things you can actually directly do.

Say yes to the power of Diplomacy and bow in front of him

used to do it, then the GM started to find way around it, then i started trying in-character dialogue.