There is no way to say that Barcelona played badly against Inter Milan in the Champions League match. Barcelona performed well in both matches and were able to dominate to some extent. However, Inter Milan was lucky. They were able to secure the victory until the end. Barcelona lost due to the poor performance of Barcelona's defense and goalkeeper.
Barcelona will want to win both the Champions League and La Liga titles next season. However, it is now more difficult for Barcelona. Because Real Madrid is trying to strengthen their squad. Dominating La Liga will not be easy for Barcelona this season. Also, the Champions League is always fiercely competitive.
Barcelona's performance against Inter Milan was incredible, although I understand some people were expecting them to win the match, and since they failed to win against Inter Milan, they are saying Barcelona performed poorly in that match. If not, your obvious Barcelona performance was very good; I think luck wasn’t on their side. If not, everyone knows their performance against Inter Milan was not bad.
Barcelona will do more than they did last season in the next coming season. I’m expecting Barcelona to top both the Champions League and La Liga competition. They are strengthening their squad currently to make sure things go well for them next season. They will continue from where they stopped last season, and we will see a better performance from Barcelona.