Another note to add here: The whole system was stupid, too! What do you mean, I can only give answers, but not comment?

While there is much more to say about SO's demise, the "interaction" on the platform was definitely not one of its strengths, either.

Comments have less visibility in moderation. This has made them spam / link farming targets in the past.

A lot of people come to Stack Overflow with the mindset that it is a forum to discuss something and have tangential discussions in the comments.

https://stackoverflow.com/tour

> This site is all about getting answers. It's not a discussion forum. There's no chit-chat.

The "no comments until you get a little bit of rep" is to try to help people realize that difference from the start.