While I understand the concern you are expressing here, the plain fact is that, when it comes to foundational habits of living, there is no sharp divide between one's life as a professional and one's non-professional life. Obviously the ACM shouldn't be telling anyone how to vote or policing the way they spend their leisure time, but that's not what's happening here. Rather, this section offers an articulation of some core values and practices, of the sort that constitute the backdrop of how any person lives and thinks (or don't, as the case may be.) They are not decisions a person makes in a given moment; they are the basic architecture that sets the conditions for how one makes decisions, and that sort of architecture cannot be assembled and disassembled when one shows up for work in the morning. Honesty, respect for others, and a desire to avoid harm are deep habits of character: and like all such habits, they are reinforced by practice. This section is essential inasmuch as it recognizes these basic realities of human character
And here's another thing: how is a professional of any kind going to be able to engage in even the most basic moral reasoning, if there isn't some kind of core of shared principles from which to reason? How are we supposed to assess the potential harm that (for example) the privacy settings a social media app might cause unless we are prepared to think about the different ways in which privacy is a basic quality of life issue? Saying "privacy is good and/or important" doesn't get us very far unless we can talk about why. And the only way to offer those sorts of arguments and defenses is to appeal to basic moral concepts that are beyond the purview of the kind of narrow professional code you are suggesting. Without broader moral principles, a professional code is like a rootless tree; it will blow over in the first strong wind.