Note I say destroy, and not jettison/sell (generally).

With a patch to overstuffing on the horizon, and a need to deal with capital ships too full to dock with, I was thinking this could be a pretty decent way to deal with a post-overstuffing world with some other nice benefits. All it would be is a button from the inventory menu allowing you to permanently delete an item from your inventory. It could be in any station, ship, etc.

Benefits:
1. Assuming overstuffing is gone and you can no longer dock with a ship at max cargo, this would be a way to let yourself back in.
2. Similarly, if you fly with a bunch of ships and your friends can't dock, you can destroy one of the ships in your inventory to make room.
3. Some item(s) stuck in a station that you no longer have access to/is far away? Delete it for peace of mind/ease/etc. I imagine some poor guy is stuck KOS with a faction or two and is paying rent on those stations essentially indefinitely.

Drawbacks/caveats:
1. I think this needs some sort of limiter: either time, credits, or both. Perhaps the cost/delay between usages of this ability would grow very quickly, only coming down after a good while. For one, having this be some sort of free inventory cleaner would mean there's no practical benefit to planning your loading. Punishing said poor planning by implementing cost or a delay would mean smart packing of your ship would still be better. Secondly, such a feature could allow a malicious actor who got access to someone else's account a really easy way to just delete a ton of valuable/unique items, so either a delay or prohibitive cost for bulk items would mitigate this greatly.
2. I think any sort of items that could normally be jettisoned should be jettisoned, rather than deleted. Otherwise you'd have players in imminent danger deleting their rare items/weapons simply to deny others the chance to loot it.
3. Similar to the above, there should be a delay or outright inability to use this option when in combat (taking or dealing damage in the past x minutes).

+1

I am not against this, but just jettisoning would be a better option, even if there is a risk of someone stealing your cargo.
As no one would want to destroy their expensive items from a wrong button, so give some very good failsafes against using it the wrong way.

+1 To remote destruction. Would be a good qol addition to the game.

So, I don't love the concept of content-destruction being too easy to execute. As the OP describes, it gets into "denial" type issues in which someone is destroying something out of spite. There are also a lot of potential ramifications and situations around this that could emerge over time (with further gameplay changes) that could also prove problematic.

That being said, something similar might be a reasonable middle-ground for the moment: to simply allow people to Jettison ships, and when they do so, they simply cease to exist. Ideally the addons and cargo and other equipped ship content would be jettisoned, but the ship-hull itself would go away.

Eventually, when all the edge-cases and ramifications of ship-hulls being objects that one can both pick-up in space, as well as jettison in space, then the ship "disappearing" would be replaced by that. So, it would effectively be an interim solution, rather than an actual design-goal.

I’d definitely be happy with the above - it was the impetus (along with people paying for storage in stations they can’t dock in, but that’s a lot more rare). If this does happen, can we have a “confirm” dialogue specifically when we attempt to jettison a ship? Sometimes my muscle memory fails me while navigating menus and I accidentally hit “jettison all” and I would hate to be stuck far from a large station in my capship because of a misclick.

Yeah, we would definitely have a confirm dialog on anything that will result in content-destruction. Otherwise, people would be very unhappy when they accidentally nuked their Superlight or rare-collectable-ship or whatever.

Even if the ship goes poof, what about making so their addons jettison?
So you dont lose a probably hard to get weapon, only the ship.
And there should be a dialog where it warns you that it will be destroyed upon jettison, only the addons will get unequipped if there is enough cargo, or jettisoned like normal cargo, without the ship.
If this is possible after all.

Even if the ship goes poof, what about making so their addons jettison?

That was why I wrote above:

Ideally the addons and cargo and other equipped ship content would be jettisoned, but the ship-hull itself would go away.

I take the time to read your posts.