I mean, they're in two finals, surely you can't call them a weak team? That would mean everyone who finished third (or less) or failed to enter the finals is a terrible team. Feels weird if you can only classify one team as a strong team every season because they won some silverware.
I dislike this all-or-nothing judgment. It would be horrible for a team to sack a coach every season if they failed to win something.
I also don't understand that point of view. People are looking at only what happened at the end. Yeah it wasn't a good ending for Inter in the Serie A and Champions League. But these guys were still one of the most successful 2 teams in both tournaments.

Inter didn't sack Simone Inzaghi after it either. He just wanted to resign and accept Al-Hilal's offer. I respect his success in the Champions League. Eliminating Bayern Munich and the strongest Barcelona in the recent years are both top works.
Inter Milan failed to win either the UEFA Champions League trophy or the Scudetto this season, which makes football fans believe Inter Milan didn't end this season in a good way. Yeah, I agree with you that Inter Milan is one of the 2 most successful clubs in both tournaments because they finished as the runner-up in both tournaments, which is difficult to achieve.
Despite the fact that Inter was unable to win any of the trophies in Seria A and UCL, they are still the most successful club because they will definitely get rewarded in both competitions. It's just that it turned out that Inter couldn't achieve any trophy but initially, they were the favorite in Seria A. The passion of winning UCL was what made them to loose focus on the Scudetto and before they realized their mistake, it was too late.