Right. We will be defending Israel from the incoming Iranian ballistic missiles after they kill innocent civilians on a scale larger than they already have been, prompting a response from Iran large enough that the iron dome is not capable of handing it. Which totally doesn't make us participants. We're not directly doing the bloodshed, just enabling it and defending Israel from feeling any consequences.
To me it seems like less of a double standard and more of a representation of the divide between Americans.
Trump gets plenty of criticism from all around. Including from the same people that are also criticizing Harris. But his voter base is in full support of the stuff he's spewing, and will believe anything he says wholesale. Even if it's crazy, or unsubstantiated, or demonstrable lies.
The people who make legitimate criticisms of Harris are not supportive of trump. But them criticizing Trump will not change Trump. He already has unwavering support from a large number of people. Why would he do anything to gain the support of someone who is willing to call him out on his bullshit and hold him to an actual standard? And it's not going to change the minds of any of his cult-like voters. However they do have hope that by criticizing Harris they might see her actually make changes towards becoming a candidate they wholesale fully support. Not a candidate that they are forced to choose because of the alternative. But a candidate that they actively want to be elected. These criticisms might also be persuasive to other Harris supporters and call them to be vocal and advocate for her to change as well.
So it's less of individuals having double standards and treating the candidates differently, but the two polar opposite standards that the voter bases have.