Most critics agree Once Upon a Deadpool is a re-edit of Deadpool 2 with the swearing and blood trimmed out, and they agree the new material is the only reason to watch. The framing device, in which Deadpool reads the story to a kidnapped Fred Savage in a nod to The Princess Bride, is praised almost everywhere as the highlight; several reviews call the cutaways funny, nostalgic and pleasingly stupid. Ryan Reynolds gets credit for keeping the jokes afloat, and the charity tie-in is noted approvingly.
The reservations cluster around whether the film needed to exist. Most reviews call it a cash grab, with too little new footage to justify a ticket and cuts that leave the action thinner and the pacing choppy. The spread is fairly narrow, from lukewarm to hostile; Polygon is the sole clear supporter, finding enough laughs to forgive the scheme, while The Wrap is the harshest, seeing little more than a trimmed rerun.