Very interesting. I would have guessed it is a universal problem, not an issue with the specific piece I own.
I found a quite interesting workaround, though. I connected a wireless keyboard to the USB port and use that now for controlling the TV. The result concerning key press responsiveness and reliability is absolutely impressive. No lost key pressed at all and (guessing) at least 5 times faster responses. After trying that out I can't imagine why anyone (who knows about that option) would still choose to use the crappy remote.
Of course it has the drawback that not all remote control keys are directly mapped to PC keyboard keys. Particularly annoying is the Amazon app, which makes heavy use of the 'color' keys, which seem not to be reachable at all via PC keyboard. Also text input for the Amazon app (like for the search function) doesn't accept PC keyboard letter keys. This seems to be a Amazon-specific problem, though.
What I wish from the OS itself now, would be to map the missing remote keys to PC keyboard also. Preferably allowing for used-defined mappings.