Well, yes, but it must also be said that due to the poor timing of Conte announcing his departure, which left us in a real hurry to find a coach for the upcoming season, our board wasn't left with a whole lot of options. They took a gamble on Allegri, a coach that had won Serie-A in the past, and all things considered I think appointing him was a logical choice at the time that was justified.
Sounds like I'm completely giving up on Allegri right now, which I'm not, but it's more about what I fear (that he's not the right man for the job). Of course, if he isn't, you're right that the board is to blame, but we shouldn't entirely forget about the difficult position they were put in at the time.
Hopefully, though, they're keeping Allegri on a very short leash and are considering candidates to replace him constantly behind the scenes, in case he proves not to be un allenatore da Juve.