According to the Rittenhouse verdict you don't need to own the property you are defending (or even be in the same state as your own property) to kill a guy if you think that guy is trying to take your gun.
Maybe if Arbery had been a convicted sex offender people could have seen the upside to his murder.
Rittenhouse was defending himself when he shot, not property. He was being actively attacked each and every time he pulled the trigger. He also pulled the trigger at literally the last possible second available to him. And it's all on video. These are very different cases and that's why you have very different verdicts.
Think of it this way:
The entire time that Rosenbaum is chasing Rittenhouse across the parking lot, Rittenhouse is making every attempt and doing everything in his power to make sure that no one gets hurt. Not just himself, but Rosenbaum as well. He has a rifle with him. He doesn't have to run. He can protect his own safety without running. He runs to protect Rosenbaum, even as Rosenbaum is trying to attack him. That entire time, Rosenbaum has it in his power to end things without anyone being harmed. If he stops chasing, everyone goes home and nobody gets hurt. Not him, not Rittenhouse. But he pushed it until forcing Rittenhouse into a choice between risking being harmed and killed himself, or pulling the trigger and harming (and killing) the person attacking him. Rosenbaum pushed that decision on Rittenhouse. The jury saw that and acquitted him.
The Arbery case is the exact opposite. Like Rosenbaum, the three men chasing him could have stopped chasing at any time, and no one gets hurt. Everyone goes home alive. Arbery (like Rittenhouse) did everything in his power to escape the situation without anyone getting hurt. But the men push the action until they force Arbery into a decision of fighting for his life. Unfortunately, unlike Rittenhouse, Arbery did not have a gun of his own and ended up the one who was killed. The jury saw that and that's why they found those men guilty.
The facts of the case itself matter. You can't just go around making decisions of whether a person should be convicted of murder and thrown in jail for long periods of time, or be acquitted and allowed to walk free, based entirely on what you think of their politics. There are an awful lot of people who seem to think that's an okay way to go about things. It's pretty damned frightening.
Let me state that more clearly. The opinion you stated above isn't simply wrongheaded. It's terrifying.