Alistair Ryder’s review published on Letterboxd:
Everything that's wrong with "Lightyear" can be traced back to its very opening title card. Pixar's latest effort opens with onscreen text informing us that the film we're about to see was the favorite film of the human "Toy Story" protagonist Andy, his love for it inspiring his parents to buy him his very own Buzz Lightyear action figure. Director Angus MacLane, in his solo directorial debut, has gone even further in developing the lore around the space ranger. That action figure we're introduced to in "Toy Story" isn't from this film, he has argued in interviews, but instead tie-in merchandise to go along with the spin-off animated series that was created after this film's success within the "Toy Story" universe. Confused yet?
This convoluted explanation to the film's existence might initially sound like something that can be easily overlooked, but you don't have to be a nitpicking viewer of the Cinema Sins variety, ticking off all the movie mistakes rather than enjoying the film, to find that it overshadows your overall enjoyment. After all, what we're watching is essentially an origin story for the Buzz Lightyear character — so why does it feature so many winking meta nods that make no sense if they're pre-dating "Toy Story"? And why does a film that, within the franchise timeline, was made somewhere between the late 1970's and mid 1980's feature several scenes no conservative studio head would have allowed to be included as recently as five years ago? In any other film, these aspects would be a positive — but here, they merely emphasize that MacLane struggled to rise to the challenge of making an authentic post-"Star Wars" sci-fi blockbuster. The in-universe timeline proves to be an unnecessary constraint on what would otherwise be a fun (but admittedly throwaway) romp.