Often installing a package would pull a bunch of other dependencies into the system.

But they won’t get removed by default when you remove the original package you installed.

In Debian world there is “apt-get autoremove”

Actually Yum has a config option to turn on auto removal!
Just add this line to your /etc/yum.conf

# Auto remove dependencies on package removal
clean_requirements_on_remove = True

Then yum will to remove unnecessary dependency automatically from now on.

For existing packages,  it will require a bit of manual labour.

package-cleanup --quiet --leaves

Carefully examine the list and manually remove them