Those are both very bad reasons for making commenting private.

1. A downvote system is sufficient to catch spammers, with explicitly moderation needed for edge cases. (And those edge cases would be applicable even in private commenting)

2. Harsh feedback is discouraged on Product Hunt because of the elitism. Having comments public will not discourage it. (C.f. Hacker News)

oops, i forgot to mention the real reason: lack of time for v1 :)

adding a real commenting system is on the table for sure, ill create a github issue for it and we can discuss with the community about pros/cons

> encourage honest (harsh) feedback that the product owner can take action on.

I think this is a solution to a problem that doesn't exist.

If there's one thing I know about "Show HN", it's that the community doesn't hold back on its criticism.

Comments are one of the main ways you're going to foster a community.

An alternative would be to allow comments to be shown privately or to have a messaging/mail system.

Hiding them by default is a big mistake.

agreed, we'll be adding public comments to the site soon (in addition to private feedback)