It's funny, isn't it that how the landscape of perspective changes so suddenly. Given, Barcelona has a very strong, albeit aging squad, they won zilch in 16-17 season under Enrique. In comes Valverde, does the basic things right, Barcelona wins La Liga on a canter, but still he is being vilified as if Barcelona is near relegation. Just based on one bad game in UCL. Same this season. Of course Valverde is pragmatic and stylistically do not match Barca, but he is doing his job as asked.
And this Barcelona style, in my opinion, is far over-hyped. Barcelona gained world recognition during Cruyff, then spent another 10 years into oblivion (although winning La Liga under LVG), and then had substantial success under Rijkaard and especially Pep. Pep's reign has clouded people's perception that Barcelona's identity is Tiki-Taka. Even Luis Enrique played a different style.
Ultimately, winning silverware matters. United supporters would stop complaining about Mourinho if he wins them the PL with his boring style. And that is the same reason they and others use when dissing Klopp, as his Liverpool has failed to win trophies.