The secret of "Reacher's" success is that it doesn't pretend to be something it's not. The show offers a good ol' murder investigation, with plenty of people getting beat up in the process. As many reviewers have noted, it's a prime example of "dad television," i.e., a TV show that feels like something your dad would watch and then try to talk to you about when you visit for the holidays.
Eric Deggans of NPR goes all in on the "Dad TV" descriptor and how Amazon Prime Video has cornered that market with shows like "Tom Clancy's Jack Ryan" and "Bosch." That same goes for "Reacher," which Deggans praises as "an entertaining ride that takes a compelling character through an adventure filled with wish fulfillment, fistfights, a dollop of romance and heroes crusading for justice. And, in the end, that's pretty much the core mission for most successful examples of Dad TV."
Nick Clark of the London Evening Standard was of a similar opinion, saying, "If dad rock was a TV show, this would be it. And it's rocking amazing." "Reacher" doesn't pretend to be anything it's not. It's the kind of show to turn on at the end of a long week with a cold drink in hand to unwind for a little bit. And while some fans think Jack Reacher needs more realistic opponents, it doesn't seem to be hurting his reputation among critics or audiences very much.