Iniesta was finished by 2015/16. He was one of the reasons along with Busquets and Rakitic why we got absolutely canned in away CL games.
Wth? No. Iniesta still provided loads of key passes and created chances which is what we are missing today. Not to mention his ability to dribble and move into spaces was vital, as well as his quick thinking and creativity, which helped Barcelona unlocked many defences. He probably wasnt as good as his prime but he still proved to be absolutely vital in the CL (Chelsea, Roma, Juventus, Atletico).
Enrique didnt rotate the front 3 enough, wanted the unbeaten streak and that's when we even lost a few league games like Liverpool did. The whole MSN didnt play well so you cannot expect the midfield to perform. Neymar kept playing that deep role so it didnt help either. Playing Gomes in some games proved to be a huge mistake too, (missed too many chances.)
Come 18/19, Messi was doing the job of a attacking mid and a second striker. He created literally almost every goal or was the one to score it. Alot people say that Suarez was useless in the setup, but analyse the match, Suarez provided alot of threat and created alot of space for Messi to run into and score. Opponents were marking Luis because of how powerful and and dangerous his shots are. Somehow both complemented each other which is why Messi had an easier time doing the job of two men.
We got humiliated because valverde opted for less attacking options even when we had a winger then, and kept the 4 men midfield which didnt help when we tried to go forward.
Yall just here just thinking he's old and slow so he's definitely bad, when in fact he is actually better than many of the attackers signed by Bartomeu nowadays. I reckon even Iniesta will still proved to be useful till this especially looking at the state of Barca this days. Only Messi is creating and the rest is looking futile. You can have the legs to run all game but if you cannot do shit with the ball you are practically useless as well. (Griezmann for example)
Iniesta was still very much a crucial player then.