He is stirring up a discussion of how some NATO members are not paying what they agreed to. That isn't irresponsible.
Here's the most recent commitment by the NATO states:
It contains a lot more than just points 27 & 28 (defense spending). For instance, points 7 through 18 are about various NATO commitments to Ukraine against Russia.
You agree that these commitments are binding, right? All of the commitments?