I don't think this is a 5-star movie but it deserves it on here because it def isn't 3. Personally I would say it is like a 4.2. There is a lot I am not crazy about but ultimately it was a nostalgic movie that told us an entertaining story. Critics seem to hate giving the audience what they want these days and just want to have their expectations subverted. Sometimes it's nice to just see our heroes be heroes and the villains be villains and not some metaphor for the state of our society.
I think this movie will end up being very important in the years to come, as will The Last Jedi, to demonstrate the divide between the audience and critics that can exist. While this isn't new by any measure it has never involved a fan-base this passionate (and at times toxic, though I firmly believe the toxic members are a minority). There is nothing wrong with a familiar feel-good movie that gives the fans what they want as seeing our fantasies play out on the silver screen can just be a warming experience often overlooked by critics. They claim that these fantastical stories are formulaic yet stories that 1) Deliberately aim to subvert expectations 2) Create metaphors for the state of our society and 3) Build a narrative that focuses on a popular social issue in the real world... sounds an awful lot like a formula to appease critics today. Plus you can only subvert expectations as a director so many times before people begin to just expect you to try to subvert expectations (e.g. M. Night Shyamalan). Cinema in many ways is art but first and foremost it is entertainment, this is because most people are just looking for a good time not wanting to analyze the nuances of the film.
Bonus Comments regarding cinema formulas:
On average there is a lower discrepancy between critic reviews than fan reviews. This means that critics often agree more on what is a "good" movie and what is a "bad" movie. This implies that there is actually always a formula (relative to the time the movie was made) to appease critics. Because the average audience can disagree wildly "formulas" don't really work on the audience as a whole, they are however effective on fanbases. TLJ split the fanbase because many of us really liked about 40% but almost 60% of it was trash, that 60% was appealing to critics where they "subverted" previous plot points, told a completely pointless side-story with poorly written characters regarding corruption that was also a poor representation of real-world corruption, consistently pushed the social agenda that "anyone can be great" and just overall slowly dragged along.