I actually read through the ruling and it says this would not apply to things the president thinks is official but is clearly intended to be for his own benefit.
Let's take this a piece at a time.
Before getting to the ruling, let's start with basic English. If neither you or I commit a crime, we cannot be prosecuted. That's not immunity, that's how the rule of law works. So immunity has no application unless someone does in fact commit a crime, which means that when we say someone is immune from prosecution in any sense under any circumstance, that by definition means they cannot be prosecuted even when they do commit a crime.
So what does the ruling say. Let's start with page 4:
"The first step in deciding whether a former president is entitled to immunity for a particular prosecution is to distinguish his official from unofficial actions"
This is where I think some of the left wing commentary might be a bit hyperbolic. While the source of their concerns are valid, I don't ultimately think any court would rule that sending in steal team 6 to assassinate a political rival would pass this test. But here's the problem:
"In dividing official from unofficial acts, courts may not inquire into the president's motives"
This is perhaps the single most absurd line I've ever heard in a legal opinion. In almost any alleged criminal violation, what makes the difference between whether an act was illegal is the person's intent. Intent is the difference between someone who accidentally walked out of a store with an unpaid item vs shoplifting. With regards to a president's conduct, his intent is in most cases is the very thing that determines whether his actions were within his authority, and yet the SC just ruled that this can't even be questioned.
Let's combine that last line with this next gem:
"The indictment’s allegations that the requested investigations were shams or proposed for an improper purpose do not divest the President of exclusive authority over the investigative and prosecutorial functions of the Justice Department and its officials. Because the President cannot be prosecuted for conduct within his exclusive constitutional authority, Trump is absolutely immune from prosecution for the alleged conduct involving his discussions with Justice Department officials."
Let's be clear about what this says combined with the above. If Trump's motives can't be questioned, and his discussions with his DOJ officials cannot be questioned, then literally he cannot be prosecuted for anything he says to them so long as he colors his words with official conduct language. There is therefore no avenue for a prosecutor to bring any charges against him for it because any evidence or even argument they can make would be automatically tossed in the trash according to this ruling.
And if that goes for his conversations with the DOJ then it absolutely applies to his conversations with the military.
So you tell me, if the president orders steal team 6 to assassinate his political rival for "national security"... How does he get prosecuted for it?
And that's the easy one. Perhaps next you can explain what stops him from selling presidential pardons.
