If you crash the client the server still holds your character in status to make sure anything you may have done is accurate and checked against server data, and not a hacker trying to dupe items (there are plenty of skilled people using all kinds of tools to dupe or hack constantly, if they could find any loophole they would abuse it hard to make as much money as possible). It holds your connection way longer actually when you don't properly log out. It will perform extra checks when you log back in too, so you're not really winning anything.

Also there are local user file saves that happen when you logout or zone and that stops those happening.

The only reason anyone would complain about the 30 second logout is if they want to log between characters, crashing the client makes that worse.

Again it's an anti duping system, they are just not going to change it. The game has a 56k data cap still too, where it takes more time to transfer inventory data to the server to check etc. Once of the reasons the mog wardrobes only allow specific kinds of items (gear) is wardrobes would have potentially increased logout timer if you could fill it with items that can be split.

Don't argue nonsense.