They still have a long way to go to make that happen, but even though they look more prepared now, it's not a guarantee that they will continue to show the same. The reason is that last season they were also good but they lost their balance when the season was about to end and in the end Barcelona could freely win the title last season.
This is just the beginning of their long journey and there are still many matches left. Especially in the Champions League, big teams from each league are waiting for them to stop them in the Champions League. Although their strength now looks strong, they still need to improve.
Champions league is A Very competitive league if not the most competitive in the whole of Europe, it's normal for most teams to be outstanding at the beginning of the league because they usually have their form intact especially the bigger teams.
Buy it's usually not a guarantee that they would survive till the end and win the title, some even crash our at certain stages.
With Barcelona I feel they will improve and even get better especially by January when most of their injured players would be back and probably in better form, also they can aswell use that opportunity to strengthen their squad if they have the financial capacity, so they still have some more time.