Don't go there. Pep has nothing against Messi. His problems were related to clashes with Rosell administration. Pep never showed anything but awe and praise on Leo, that talk is pure BS.
Messi was never defensively involved since Rijkaard era. Remember him being constantly injured earlier on, Pep and Tito introduced the attack only Messi version. And once the false 9 role it was done deal.
I know that the role of the false nine was created for the following reasons:
1) Leo did not participate properly in defense.
That is, he often did not finish his defensive work on his flank. And by moving him as far away from the goal as possible, you to some DEGREE neutralized the negative impact of his poor play without the ball on the team’s defense.
2) Leo did not follow the principles of positional football, he likes to move freely. Remember the story of Henry, when Pep replaced him at half-time in a match in which he scored a goal due to the fact that he often moved out of his position.
So, when I say "Leo didn't contribute properly defensively (we're talking about the period when Pep just arrived)", I don't mean that he was as bad off the ball as he was in 2012-13, 13-14, etc.
Yes, he didn’t run like Pedri or Villa without the ball, but that level was more or less tolerable. The problems began later, when he began to become even more lazy.
I know all this very well. You don't have to tell me about this.