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.
The thing I that most players at Barcelona are very versatile and can adapt comfortably to any positions they're played in and then if the preferred players for that position fails to impress the coaches in the training ground the coach could be left with picking up players that are capable of delivering even though it means them playing out of the preferred wing, that's you'll see a Gavi deployed from the wing when they've got Ansu Fati and Ferran Torres.
Well asides that the squad looks really balance this season and would likely perform better than they did last season even though they don't look strong enough to win it yet compared to other teams like Realmadrid, Bayern and Mancity, that's got more experienced champions league players in their team, however they've got the talent and there are still some players in the squad that are experienced in the Champions League as well.