That's actually not true. People overuse the word "gaslighting," but this is actually a perfect example of the original meaning of the term.

This is the second time recently he's "accidentally" posted on something I wrote, and both times, he switched away from one of his commonly-used alts, to a different one that I didn't have blocked, right before posting. I can, if you want me to, send you the output of this from my system:

WITH target_people AS (
  SELECT id, actor_id
  FROM person
  WHERE name LIKE '%UniversalMonk%'
)
SELECT 
  action_time as timestamp,
  actor_id,
  item_id,
  score,
  creator_actor_id,
  CASE 
    WHEN score IS NULL AND content IS NOT NULL THEN 
      CASE 
        WHEN length(content) > 20 THEN substr(content, 1, 20) || '...'
        ELSE content
      END
    ELSE NULL
  END as content
FROM (
  -- Comments
  SELECT 
    c.published as action_time,
    p.actor_id,
    c.id as item_id,
    NULL::smallint as score,
    creator.actor_id as creator_actor_id,
    c.content
  FROM comment c
  JOIN target_people p ON c.creator_id = p.id
  LEFT JOIN person creator ON c.creator_id = creator.id
  WHERE NOT c.deleted AND NOT c.removed

  UNION ALL

  -- Posts
  SELECT 
    p.published as action_time,
    person.actor_id,
    p.id as item_id,
    NULL::smallint as score,
    NULL as creator_actor_id,
    NULL as content
  FROM post p
  JOIN target_people person ON p.creator_id = person.id
  WHERE NOT p.deleted AND NOT p.removed

  UNION ALL

  -- Comment votes
  SELECT 
    cl.published as action_time,
    p.actor_id,
    cl.comment_id as item_id,
    cl.score,
    creator.actor_id as creator_actor_id,
    c.content
  FROM comment_like cl
  JOIN target_people p ON cl.person_id = p.id
  LEFT JOIN comment c ON cl.comment_id = c.id
  LEFT JOIN person creator ON c.creator_id = creator.id
  WHERE NOT c.deleted AND NOT c.removed
) combined_actions
ORDER BY action_time DESC;

So what it shows this time, is UniversalMonk using his sh.itjust.works account and lemmy.dbzer0.com account and nothing else for a few days, including most recently at Feb 12 at 23:27, and then at 23:36, switching to his r.nf account, which I haven't blocked and which he doesn't use much, and the first thing he did with it was comment on a post of mine.

The previous time was actually even a little more egregious. He was using his other accounts (including his lemm.ee one, before that one was banned), then at Feb 4 at 21:04 I made a comment in some thread mentioning the existence of a new alt of his, and he switched from other actions on his mainly-used accounts (most recently at 21:38) and then at 21:39 from his vegantheoryclub.org account, his first action on that account was to post this:

https://vegantheoryclub.org/comment/1670126

Then, when I semi-politely told him that he was evading the block (since it was pretty obvious to me that something along the lines of the above had happened, although I didn't verify it at the time) and asked him not to, he played the exact same game of pretending he had just innocently stumbled across a post of mine and wanted to say something about it, and it was totally unreasonable for me to ask him not to.

There's a reason he switches to an account I haven't blocked right before leaving these comments. And yes, I know it sounds semi-psychotic that I went digging around in the database to verify that he is gaslighting you when he feigns total shock and surprise that he had left a comment under a post by me, pretending it was total coincidence. This is why he keeps getting banned on different instances: His behavior is really very strange, dishonest, and malicious in a kind of unique way.

Anyway, yes he was block evading on purpose to minorly irritate me. I'm happy to DM you proof excerpts or similar. I know it sounds kind of petty for me to go to this extent, but the other way to look at it is, this is the extent that someone has to go to if they want to not be communicated at by UnviersalMonk. He has a history of targeted harassment of users in the past (which is what got him banned from lemmy.world), and for me he seems to have chosen this kind of "gaslighting and hoping I'll complain about it, so he can feign innocence and write a big italicized innocent message" approach.

I've seen them posting in communities and instances they have previously been banned from. If they made an attempt to avoid it that would be one thing but they don't.

I'm almost certain they are ban evading with their alts.

What in the actual fuck are you talking about? The user is deliberately block evading. Its so bad, I am going to start publishing a daily UM blocklist for people.