It's one thing to have a UEFA Champions League experience as a player and also a total different thing to have it as manager but some persons are mistaking it when talking about Xavi Hernandez's champions league experience.
Barcelona is his first club that he competed in the competition with and that's why he shouldn't be blamed to an extent on the club's performance last season in the European Cup. He's been progressive with his Barcelona team and might win the Champions League in the nearest future if he's allowed to continue to develop this Barcelona young team
The current Barcelona squad won't win the Champions league unless a miracle happens, maybe it would take five miracles in one season. They don't have this continuous dominance yet. It could still be possible that they make it through the group stage and then also survive in the competition for one or two rounds, but if they were up against Manchester City or Real Madrid tomorrow, I think it would be pretty safe to say that that is where the journey would come to an end for them.
Even I also agree about this Barcelona can't win Champions League into this season but still now they are much better and experienced for having spot into knock-out stage and most chances they will be not knocked-out from group stage like last season because now situation is completed change and their players are having better depth with their strategy is also working which helping them for having better results and building a unit which will have good development for long run.
Now this season is surely going to have few good things as Barcelona is learning from mistakes and their targets are also changed with in last season their main focus was La Liga, but now they are also thinking to achieve better in Champions League this change of mind is going to help them.
I disagree with the statement that barcelona has better squad depth now because in fact Xavi often uses Gavi as a winger despite Ansu Fati and also despite Ferran Torres but Xavi prefers to use Lamine Yamal for the same position. This is clear when they have played a number of domestic league matches and in fact it has gone quite well and if Barcelona had good players for that position it would be impossible for them to risk players who are not in their proper positions or even install their academy players to be able to cover the gap. I think Xavi's rotation is very limited with the options available now and they need to have real targets to go further in the Champions League this season.