What benefit does it allow for, other than the ability to turn the country into a dictatorship in a matter of hours with a single phone call?
For anyone unaware, one of the main criticisms of that ruling is that the president commanding the military is always considered an official act, and this ruling means the president enjoys "absolute immunity for official acts within an exclusive presidential authority that Congress cannot regulate such as the pardon, command of the military, execution of laws, or control of the executive branch."[0]
The ruling made no carveouts or exceptions for blatantly illegal orders. The president could unilaterally eject or kill any member of opposing political parties and future administrations (if there are any) would be completely unable to legally hold them accountable for their heinous crimes.
The benefit is that the president is not subject to retaliatory lawsuits (similar to what the Trump administration is now doing against e.g. James Comey, et al), the threat of which might prevent them from performing their duties effectively while in office.
I’m sympathetic to your concerns, agree that it was a poor ruling, and frankly think we need a constitutional amendment to address the excessive power the presidency has, but the justices aren’t making these rulings without having a real, justifiable rationale behind them and they aren’t making these rulings because they’re in the tank for Donald Trump (Justice Alito excepted)
For anyone unaware, one of the main criticisms of that ruling is that the president commanding the military is always considered an official act, and this ruling means the president enjoys "absolute immunity for official acts within an exclusive presidential authority that Congress cannot regulate such as the pardon, command of the military, execution of laws, or control of the executive branch."[0]
The ruling made no carveouts or exceptions for blatantly illegal orders. The president could unilaterally eject or kill any member of opposing political parties and future administrations (if there are any) would be completely unable to legally hold them accountable for their heinous crimes.
[0]: https://en.wikipedia.org/wiki/Trump_v._United_States