I haven't personally seen the OOM killer kill unproductively - usually it kills either a runaway culprit or something that will actually free up enough space to help.
For your "even for systems with half a terabyte of RAM", it is logical that the larger the system, the worse this behaviour is, because when things go sideways there is a lot more stuff to sort out and that takes longer. My work server has 1.5TB of RAM, and an OOM event before I installed earlyoom was not pretty at all.
Made me really not mind having a little swap space setup just in case.
Discord is great for chatting with your friends, gaming, etc. but man it's a horrible knowledge repository.