Brandolini's law
Brandolini's law, also known as the bullshit asymmetry principle:
The amount of energy needed to refute bullshit is an order of magnitude bigger than that needed to produce it.
As a result, your effort to debunk misinformation
is sometimes at the mercy of someone just spouting semi-coherent nonsense.
When they care more about being right than it being true, that effort is usually wasted.
So it's often worth it to figure whether the response will be listened to by them, or anyone.
It can also be worth it to mention where you believe the burden of proof lies - "I will doubt your statements until you can show me any proof / tie that into the real world" is can be a very valid response. Actually, in the form of asking questions this may be much more respected by them, more so than you talking back all the time (file under: lessons I still have not learned).