It does seem clear that Charlie Kirk was treading on dangerous ground, and making enemies (like Netanyahu who brags about assassination), but motive is not proof.
Not only is motive not proof, motive is not even an element of proof. When the cookie jar is empty and the toddler has cookie crumbs all over his fingers and lips, you don't need to suss out a motive for the caper to secure a conviction. Lots of people end up being convicted "beyond a reasonable doubt" without there ever being any certainty (or even just a good guess) as to what their motives were.
The problem when it comes to things like the case of the assassination of Charlie Kirk is that, depending on one's preferred narrative (which is ineluctable, because "the facts" do not ever "speak for themselves"), some will suspect or insist things are "cookie crumbs" that others will suspect or insist are not (and vice versa) - let alone whose fingers and lips they are on (or not).
At some point, when a sufficient "critical mass" of "the facts" (as interpreted and analyzed from this or that perspective), speculation, suspicion, innuendo, etc. has been achieved, things reach what I call the Conspiracy Theory Event Horizon - beyond which "the truth" (as distinct from "the facts"), even if it ever really came out, and whatever it might be, would just end up being regarded as merely another narrative among the rest, with no essential quality sufficient to particularly distinguish it from those others.
The JFK and 9/11 cases are exemplars of the CTEH having been crossed.
The Charlie Kirk assassination seems already to be well on its way there.
Fortunately, voters don't need beyond a reasonable doubt. They just need to decide not to reelect anyone who ever displayed a Star of David by their office door.
As unlikely as the former seems, the latter seems even more so.