Yeah, agreed but you should take into account motivation factor as well as Conte -> Allegri swap. At this point Allegri is a big gamble, especially for Serie A. I'm not worried about CL because it would be hard to do worse than Conte did last season but in Serie A Conte owned everyone.
I personally don't view Allegri as a gamble. I really like the fact that he seems happy to not tinker too quickly with our tactics. I like that he's always very composed and well thought out. I think if we decline, it will not be because he decided to radically change certain things about our squad or got overwhelmed or started making mistakes because of emotion.
I think he's a safe choice. Much safer than if we hired someone like Spalletti or Sinisa Mihajlovic for example. Allegri strikes me as the type to win Serie A by only a few points but do much better in the CL because of smart squad rotation throughout the year. Conte took every game as life or death when it really wasn't.
There's also a part of me that wonders just how long Conte's philosophy would hold up. It's hard to go 100 mph every day for 3 years. If he burnt himself out so quickly, imagine what the players must be feeling and perhaps taking the foot off the pedal just a bit could be a blessing in disguise.
The best we can do is to keep improving the squad, which we are doing, and to gradually shift into a new style of play, which it looks like we're doing as well. Then we just have to hope for the best.