I agree with you that Bayern wouldn't do much in the Champions league next season because Kompany hasn't really focused on the UCL competition last season but was more focused on lifting the Bundesliga title. The same might repeat itself next season. Liverpool looks promising because they have the squad to go far in the competition, but nobody knows if they can. Injury can also be a barrier to these strong clubs which will lead to underperformance.
It is fair to worry that their new manager Kompany might prioritize winning Bundesliga again just like he seemed to do last season which could stop them from going far in Champions League. Building strong team at home mostly comes first for new managers making Champions League secondary goal initially. While Liverpool squad definitely looks strong and capable of deep run. You are right that injuries are massive concern and we have seen best teams can have their Champions League dreams crushed if key players get sidelined when they have crucial times. And this is proving that staying fit is just as important as talent for any club aiming for title.