Something I think I noticed recently.
You could use that recent Black Mesa duplicate in the Left 4 Dead 2 area as an example.
Not exactly sure if you can even search specifically for something abandoned...

Anyway, on the main site you'd see no comments are accessible once an item is abandoned.
However, maybe it's an oversight, comments are still fully accessible on an item on the beta site.
Don't know if new ones could be made, I haven't tried, don't see a point commenting on something abandoned.
Could be something certain specific users could abuse to continue trolling and harassing others.

Regardless of comment posting ability or not, I don't think you should be seeing comments on the beta site.
Honestly, I'm mixed about abandoned items in general. Might as well just let them be deleted.
Especially if an original author (or someone else authorized to act on behalf) requests for removal.
My opinion is removal equals deletion... hence use of the word removal.

Abandoned could be defined in multiple ways.
I'd look at it from an actual real developer/author perspective, not just any random user...
Let's say a creator wanted to take some time off, but let it be more obvious for future reference.
They should be able to do so, but the item still functional as always as normal.
Continue letting it be publicly accessible, usable, but a notice remains it might not be actively updated.
A bit different from complete status because that might imply still being worked on with minor changes.
Final status is self explanatory.
Abandoned would mean an indefinite hiatus, temporary break.
Perhaps it's the wording that is misleading. Pending or Incomplete might sound better.
Abandoned could make others think someone's given up completely which isn't always true.

Another concern/issue, is I thought I once heard abandoned sets them on a timer to be purged/deleted.
This would come at a great inconvenience to many, original authors included especially.
Even if someone does want to quit on their work, they might not want to be ridden of it fully.
There could be some separate archive section for old works such as this so we don't lose them.
You never know when someone might eventually one day come around looking for a rare gem.
Sometimes there are some classics you should preserve for at least nostalgia or sentimental value.
For example, I had a couple of friends who used to make a tradition of playing "Coal'd Blood" in Left 4 Dead.
It was one of their all time favorite custom campaigns, if not their number one favorite.
Sometimes you just enjoy going back and reliving good memories like that.

Not sure why this old topic was bumped, but i see who did it was banned so maybe it was a bot.
Anyway, greenhood, I believe our concerns were calling it "abandoned" is a bit misleading.
Would rather make more sense having it called "archived".
If what I was told is still correct, "abandoned" status runs the risk of being purged / automatically deleted over time.
The issue is, what if... yes, an author no longer wants to continue development, but also doesn't want the item removed?
Having an 'archived" status would allow the item to remain preserved over time.
Think of like setting the already existing statuses like "complete" and 'final' on the old site (there were even descriptions for them).
Except now it would hopefully make actual development status even more clear and understanding.