Try an App search on the f-droid.org website for “contacts” returns the following results as you might expect;
Fake Contacts, Simple Contacts, Export Contacts, Import Contacts, My Contacts, Identiconizer, K sync, LDAP sync, Recent Contacts Widget, Open Contacts… etc.
Now do the same search in the f-droid app;
Nextcloud Talk, Open Contacts, CTemplar, Nextcloud, Tutanota email, Emerald Dialer, Yet Another Call Blocker, Simple Dialer, SimpleLogin, Smoke, XClipper, DAVx5, Asastus-Photon,
You can see the f-droid app search only returned one result that is relevent to the search word “contacts” even though there are multiple contacts apps.