But that's exactly the problem.
Who wants to think they're on the nefarious side?! Pretty much nobody. So who is going to buy that the actions "speak to" something more nefarious? Why, the people who already were most strongly opposed.
But you already had them. You're just preaching to the choir, at the expense of sounding believable to others.
Furthermore, the problem with "reading between the lines" is that it's very very tempting to put there those things that would make one correct, the morality clear, the cause just, etc. etc..
It's absolutely good to do the deeper thinking, but most of it should be, "What if I'm wrong? How can I know? In what ways could I have I tricked myself, and if so, what will reveal the trick?" unless you are comfortable with a high error rate.
I'm not. I'd rather not know than "know" a bunch of things that are wrong. (There are a lot of things that I don't know. And even so, I'm sure I believe a variety of things that are false. But I'm quite sure I'd believe a lot more false things if I were less careful.)
The point about de-escalation only holds if you need to build consensus with people who don't entirely agree with you. When you need to, you'd better not antagonize the people you're trying to reach.
And--point 3--don't rely on any reading between the lines. Spell it out. Back it up, at least if challenged.
Some things can't be backed up, if one must read behind the lines. But is that really necessary here?
Suppose that nobody of any influence in Israel has anything but horror at the idea of genocide against Palestinians. It's the last thing they want to do. Heck, suppose that it's not even retribution! Suppose it's only action taken to eliminate the threat as quickly and effectively as possible so it's no longer a threat.
Suppose it's only that, nothing more.
Does that bring the 20,000+ civilians back to life?
It does not.
You don't need any more for it to be a matter of critical urgency to find a better way. You do, however, need a credible alternative.
If you can demonstrate conclusively that some of it is retribution, the credible alternative is trivial: "stop exacting retribution".
The moral case is already plenty clear there, without need to convince anyone of deeper nefariousness than that.