Lemmy let's you un-delete anything you've deleted, so nothing really gets nuked (it seems to be the way these things work anyway, that it's just a 'deleted' flag that's flipped between true and false).
On the one hand, it's a Lemmy problem - I can see you're comment using the API:
curl --request GET \
--url 'https://lemmy.world/api/v3/comment?id=8986376' \
--header 'accept: application/json'
=>
{
"comment_view": {
"comment": {
"id": 8986376,
"creator_id": 399371,
"post_id": 13748490,
"content": "See what i mean? I deleted this!",
"removed": false,
"published": "2024-03-31T09:48:22.897008Z",
"deleted": true,
"ap_id": "https://lemmy.world/comment/8986376",
"local": true,
"path": "0.8986376",
"distinguished": false,
"language_id": 37
...
But there's also a bug with Sync in that it's not checking the flag if someone try to reply.
If it's something you feel strongly about, then for this reason, and the usual federation reasons, it's probably better to overwrite your content with "[deleted]" or something, rather than delete it.
(you may have already seen this - my original reply went to the wrong place. Which is another Sync bug incidentally, when using the notification to reply (Android))