* Unitary executive theory. Congress can't create a federal reserve, except for when the supreme court likes it.
* Major questions doctrine. Congress can't create an EPA and give it open ended authority to regulate its way to clean air
* Qualified immunity. Congress can't stop ICE agents from murdering people
* Historical tradition as regard to the 2nd amendment. Congress can't ban everyone from walking around with military assault weapons.
I don't see how Congress can easily fix this.