That seriously needs to be one of the first patent reforms implemented here in the US: If you aren't actually using a patent, you can't sue anyone over it. Then gradually extend that to where, if you don't use a patent within a period of time (say 2-years) it is considered abandoned and put in the public domain. You have to actually be selling some kind of good or service that uses the particular patent to be able to sue anyone over it, and if they "infringed" upon the patent before you started selling anything that uses it, too bad, it's considered two entities arriving at the same conclusion independently of one another.
None of which will do anything to harm patent enforcement for companies actually making and selling products/services that make use of their patents. If anything, it'll help unclog the courts so when they have a legitimate case to bring, it'll get heard and resolved faster. And as a side note, I can barely think of a worse job than being a judge who has to sit and listen to these kinds of cases all day, every day. You can't just tune out either, you have to be actively engaged for when one side's lawyer objects to something the other side's lawyer said. That just seems utterly exhausting. Like dealing with bickering adult toddlers all day long.