They referred to 4617(f) as "the anti-injunction clause". That means it stops injunctions.
Your only hope for it to not apply to warrant exercise or senior-to-common conversion is for a court to hold that those things actually exceed FHFA's powers or functions as conservator. But FHFA as conservator controls all actions of the boards of directors, which include the ability to offer the conversion.
If you try to get an injunction against warrant exercise you will be laughed out of the courtroom. The warrants have existed since 2008, do you honestly expect a court to accept the argument that you never expected Treasury to actually exercise them?
To truly stop the warrants from being exercised you need to file an injunction before they are exercised. The fact that nobody has done so yet speaks volumes.
It's not nonsense at all. The NWS hurt the companies themselves and the Supreme Court said that's okay. Treasury exercising the warrants and/or accepting a senior-to-common conversion hurts absolutely nobody other than legacy common shareholders that have no voice and no vote. The conversion actually helps the companies because it increases all forms of regulatory capital by $193B in an instant.