Kidding aside, I don't believe Tor is being specifically targeted by HN in any way. If there is any auto-banning mechanism in the codebase at all (is there?) I would think it might be IP ratelimit-based, and in that case it's possible for unlucky HN Tor users who share an IP with a HN Tor spammer to suffer collateral damage.
It's probably better to email them. They don't always see these threads.
Here are three threads from 2 years ago:
https://news.ycombinator.com/item?id=7894816#7895823
https://news.ycombinator.com/item?id=8203164#8206090
https://news.ycombinator.com/item?id=7825556
The new things dang talks about are the [vouch] link, which means users can rescue comments marked as dead, and bring mod attention to the account to turn off the dead. (I think that's how it works. I'm not a mod. Here's the comment that makes me think it works that way: https://news.ycombinator.com/item?id=10624178#10638699 )