I honestly really feel for Tata. Like I would argue that even Pep would have had a nightmare of a season here too. This year in particular, we have been absolutely hammered with distraction and after distraction. Any of just one of these distractions would have derailed any elite club, and in some ways considering how much this team has been through this last year, we should be thankful that we still have a somewhat outside chance of retaining La Liga. First it was Tito's sickness, once that blew over then we had Messi's tax evasion controversy. After Messi's taxes, it was Neymargate. After Neymargate, VVs untimely end to his Barca career that was truly unfitting for how well he was playing, then Pique gets hurt. Finally after all of that, we were still a goal away from advancing to the semis in CL and were in full command of La Liga and CdR.
The biggest nail in the coffin for our season was VV's injury. Had he been healthy for this run-in, I think the CdR and that 2nd leg at the Calderon could have played out differently with him. He was playing his heart out for us in his final season and to see him go down like that was truly tragic.
Finally you mix in the transfer ban which was a huge distraction that we had to deal with in the media and finally the death of Tito, that is roughly 8-9 instances of things really not going our way and it would be near impossible to have your players playing at the optimal level with this much going around consistently throughout the season.
Yes, Tata showed some inexperience at the European level. Yes, Tata perhaps wasn't going to be the manager that ruffled the "oldguards" feathers enough to get them playing and motivated again. But I still think Tata is a very capable coach, even though he should leave. I'd say 85% of our current problems have very little to do with his performance as a coach and in differing circumstances, Tata could have succeeded.