He was him even back in Two Guys, a Girl, and a Pizza Place.

He was already kind of heading that way before Deadpool. I rewatched Buried and he was still doing that, just with less references so he didn't sound like Gex.

Waiting (2005) was him as himself as a waiter

he was in wolverine the 2009 one as wade. hes pretty much the same thing as in deadpool just slighty less loudmouth. he did play that wierd schizophrenic character in the one movie that nobody remembers.

Van Wilder?

He did a weird indie film called "The Nines" he can turn the chops on when he wants to. I find it hard to criticise those people because "Hey, want to earn millions of dollars doing this the easy way? Or you can go do some passion projects to prove a point and make less." Is a damn awkward spot to be in.

Im sure we all like to think we would take the route of Sandler doing Uncut Gems, I love to think that was him just telling his haters to go fuck themselves. "Just because I dont, doesnt mean I cant"