How to transfer rights to a system file to another user?

Question

macOS

Looks like he did everything right.
I (Artem) can only read.
User vk - is the owner and can edit.
But for some reason I still manage to edit this file. How to transfer the rights completely? So I can't edit this file.

PS: I thought maybe the problem is that the system file. But the file is not used for writing, and “reading” is enough for him.