Sorry but that's a load of shite!
Danilo was fantastic when used last season - much better than Walker was playing over Christmas, and Pep refused to use him and just played Walker into form eventually.
Pep certainly has his reasons for that, but I dont see how anyone can blame Danill for wanting to leave afterwards. As a back up you work hard so that when the 1st choice hits a bad patch, you get your chance.
When the manager prefers to play an out of form first choice than you, it's time to leave.
Similarly, he was told (both Pep and Danilo made a lot of this) he would be used in midfield and LB when Pep signed him, and Pep has preferred Stones in midfield and Zinchenko and Delph over him at LB.
For whatever reason Pep prefers those players over Danilo, and he prefers Walker in the worst form of his life to Danilo. Fair enough if he wants to look for starting football elsewhere after spending 2 years competing for a spot.