Why There Is No Ask Me Anything on Hacker News?

Because Hacker News is not Reddit. AMA exists on Reddit and Reddit is well served for that purpose, so why pollute the Hacker News feed with it?

People are free to post anything they want on Hacker News, it's then up to the community, via upvotes and downvotes to decide if they want to see it. If you don't see AMA on Hacker News it's because people who read Hacker News, in aggregate, don't want to see AMA on Hacker News.

Simple.

There are AMA's from time to time. Typically, they involve an aspect of YC.

https://hn.algolia.com/?q=ama

Immigration attorney Peter Roberts has done several

https://hn.algolia.com/?q=peter%20roberts

They generally are just promotional content from what i remember most the time. I think that would be a bit too tacky for this forum if that were to become a regular occurrence.

They happen here. I recall at least one, from an immigration attorney.

If you want to create one, create an "Ask HN", but don't start the title with "Ask HN".

Hacker News is about the idea not the individual.

HN doesn't have subs, so consequently doesn't have AMA-specific subs, but HN does have occasional AMAs.