It’s a very local (Singaporean) slang widely used in my clique at one point.
I found myself saying “Can Is Can” very often whenever I was streaming a challenging game!
When I was affiliated on Twitch back in 2017, I had the option to have my own emotes.
I decided to turn that pet phrase into an emote and that’s when this whole “Can Is Can” culture caught on in the community!
Whenever you think you can’t do something, tell yourself #CanIsCan! Can Is Always Can!