So, in summary, what is Carnap’s accusation against Heidegger? He accuses him of trying to use assertions where only expression is appropriate—and where, given the danger involved, even expression ought to be limited to brief hints. He accuses him, in particular, of putting himself (or leaving himself) in a position where he must treat religious dread as if it revealed a being, an object—accuses him, that is, of idolatry, or (what comes to the same thing from a Kantian point of view) of putting a theoretical dogmatics before ethics. This is a very serious criticism indeed. [snip] This, I think, is enough to establish what I set out to here: not an attack on or defense of either Carnap or Heidegger, but simply a case for taking the one as a serious reader of the other.If we don’t end up in a position to takes sides in Heidegger and Carnap’s debate, however—and surely, philosophy having moved on, it is far too late for that—then what philosophical good is our conclusion? We cannot take sides in this debate in part because it has changed from a debate into a fundamental structural fact about the philosophical world as we have inherited it. Here in the English-speaking part of that world, in particular, the stamp of Carnap’s will is everywhere present. The way we “do philosophy”—the way we speak, write, publish; the way we divide our field into disciplines; the way we arrange requirements and syllabi for our students—none of this, of course, is the product of Carnap’s influence alone. But there is nevertheless no corner in which his influence is not felt... [snip]. If we can understand Carnap as having chosen among alternatives, and, more importantly, as having chosen for a reason, then we are on the road to once more attempting philosophy’s always-repeated task of relating to (knowing) itself and thus becoming free. In other words, we are on the road to once again becoming philosophers. --Abraham Stone, "Heidegger and Carnap on the Overcoming of Metaphysics."
Carnap's framework for philosophy is essentially forward-looking; even if one does not embrace his particular account of conceptual engineering, professional philosophy understands itself as being in the business of providing means toward solving problems on the way of understanding the truth or society's (mankind's) problems. Understanding Carnap's constrained actions is, perhaps, a worthy activity for some scholar (who is a specialist in, say, 'early analytic philosophy'), but it is not really at the core of today's philosophy.