We have players like Fàbregas and Pedro on the bench and people complain about lack of depth in the squad. Pep's squad was much thinner and I don't even want to name the kinds of players we used to have on the bench a couple of years ago, I bet many people on here haven't even heard about some of them.
What makes the difference right now (concerning the quality of the squad) is the fact that some of our key players have declined and haven't been replaced. I don't even want to go into tactics but as far as I can tell, our players also don't have the kind of strict orders that they had under Pep, and they don't face the same consequences if they don't follow those orders or don't play well.
The only one that really declined was xavi and puyol, and xavi's decline was more of a "Cant bring out 100% every game" sort of decline with proper rotation his quality has shown to still be top notch. We just got hit with injuries at the wrong time. Against tight defenses I've only seen a few players who can initiate attacks regularly (Iniesta,neymar,messi) and pedro and Sergi roberto who are good at the one touch build up needed for such games. Include iniesta or neymar to that squad and the game would've been much different (Especially iniesta + messi a combo we haven't seen this season at its best yet).