contact_filter.py <contacts.csv>

contact_filter.py

from sys import argv
import vobject

with open(argv[1]) as f:
    contacts_object = vobject.readComponents(f)

    contacts = []

    try:
        while True:
            c = next(contacts_object)
            if c.validate():
                contacts.append(c)
    except StopIteration:
        pass

for index, c in enumerate(contacts):
    try:
        del c.photo
    except:
        pass

with open('output.vcf', 'w') as f:
    for c in contacts:
        try:
            c.tel
            f.write(c.serialize())
        except AttributeError:
            pass

https://pypi.org/project/vobject/ needed

will read all contacts from the provided file, validate them and remove the contact picture.
i used it to sanitize all my contacts exported from android for the import into nextcloud