What are the tactics that teams and leaders use to beat cyclists from a weak team 'just' following the leader of the strong one?

On the 2020 Tour de France there was a leader for most of the weeks: Primož Roglič. His team, Jumbo, was in control of the race most of the stages and blocked many attacks from main opponents.
However, there was this other cyclist Tadej Pogačar, whose team was ‘weak’ but was most of the time with Roglič. At the penultimate stage, an individual time trial, he outperformed Roglič and made it to the first position in the overall ranking.

Long story short, Pogačar benefited from Roglič’s team to keep the race ‘under control’ and made it all the way to the first position by following the latter whenever it was possible, and then finally performing better in the individual time trial.

In general, cycling teams are very useful to the leaders, since they allow the leader to focus on following on the attacks of the principal opponents, while having plenty of support in the rest of the time. On the other hand, leaders without a strong team tend to suffer more because they tend to need

So, in an hypothetical case of a cyclist from a weak team ‘just’ following the leader of a strong one, benefiting from their work, what are the tactics that teams and leaders use to beat them anyway?