Kant predates analytical philosophy and some of its failures (the logical positivism you are referring to). The idea here is that first order logic doesn't need to be expressive enough to model the world. Only that some logic system is capable of modeling the understanding of a representation of the world mediated by way of perception (via the current multimodal generative AI models). And finally, it does not need to be complete or correct, just equivalent or better than how our minds do such.