hes actually clinically insane and its why he breaks the 4th wall alot. I think artists were making it seem as if hes literally talking to himself or the yellow boxes used in comics for dialogue
The Weapon X program did more than just cure Deadpool’s horrific cancer. It granted him a healing factor that enables him to regenerate destroyed tissue and organs at a superhuman rate. Whether it’s a paper cut or a decapitation, Deadpool can recover from it so long as his head remains intact...
insidethebox.fandom.com
Spiderman doesnt shut up cause hes legit 16 with powers and immature. Its kinda why he gets exicted to be around folks like tony stark and shyt.