Topics disk space Increased after confluent upgrade

We recently upgraded our confluent community from 6.0.1 to 7.0.1 and observed in increase in disk space of topics by 60GB with same volume of messages. When I see system-requirements there is no change in disk space of broker b/w 6.0.1 to 7.0.1.
Does anyone else faced this issue before and what could be the reason of it?

any comment would be helpful if there is something we need to careful regarding disk space usage.