SCOTUS has indeed given immunity to all past, present and future Presidents
There's a caveat though.......and that is that all actions of the President must be lawful and within the scope of the constitution
ANY President - past, present or future who has acted unlawfully or out with the scope of the constitution is liable to be investigated and prosecuted
Trump has always acted within the constitution - I am not at all sure that Clinton, Bush, Obama not Biden have - that really does leave them open to investigation and possible prosecution
And folks are wondering why the meltdown.....?!! LOL