Does dark theme implies security in an anti-malware app? [closed]

We are developing an anti-malware android application and some of the colleagues insist on using a dark theme for application UI because:

1. Many other anti-malware applications like DU, Avast, Avg and Bitdefender use a dark theme
2. It implies security.

I disagree because with a dark theme:

1. Shadows cannot be shown properly
2. With low screen back-light design details are not properly visible and it makes the app ugly
3. Dark themes remind old android versions
4. We don't have to do exactly as what other apps do
5. Material design is not that beautiful with dark color pallets as it is with light ones

There is a tie on opinions in our group and any good advice from outside the group and you, more experienced ones in this field, is really appreciated!