Probably better to post in the github issue rather than replying here.
Absolutely not.
This will like lots of other people say start witch hunts and people will absolutely develop bots and websites which scrape all that information and classify all users based on that. Like those Reddit sites where you can search for a user and see where they are active and all that. But this will be worse.
This data is already public. You can just create a kbin account and see who’s voting. Anyone wanting to scrape it already can, the only difference proposed is the Lemmy client showing it.
This is not possible with how the underlying protocol (ActivityPub) works. It has no mechanism for private votes.