The hopper minecart doesn't drop its item in some circumstances. I've tested around some different worlds. It drops correctly in my Realm, but not on my creative testing world. In both cases, the hopper minecart correctly drops its contents, but in the case of my creative world, the hopper minecart item isn't dropped. I've tried switching gamemodes as well as the default gamemode, but that didn't change anything either. I've also tried breaking it with a trident, but that also doesn't work.