One of the criticisms of Deadpool 2 (not ours, film critics) is that is... too much. Too much self-reference, too much breaking the fourth wall, too much winking at the camera, too much irrelevance.
For example, Deadpool calls enemy-come-ally Cable, "Thanos". Get it? Josh Brolin, who plays Cable, was just Thanos in the other Marvel universe movie. Ha ha! Well, not to the critics, some of who see this throwaway joke as an affront... to what? The extolled superhero movie? As if...
Anyway, we can't help but point out the one joke Deadpool missed. Throughout the movie, he references, watches, and quotes Yentl. Yes, THAT Yentl (there is no other, thank G-d). How did the writers miss the fact that the woman who sings "papa can you hear me" is actually Josh Brolin's... mama?
Well, stepmama, natch, Barbra Streisand only married James Brolin when son Josh was already 30, but nevertheless. Couldn't Deadpool throw in a "MAMA can you hear me"?
Apologies, film critics.