What kind of people read Punisher comics? I've met people who wore Punisher shirts, but when asked about the comics they seem to have no clue what I'm talking about.
I did. The Punisher runs that became famous were the ones that treated Frank like a killing machine and gave a bulk to the character development to Frank's foes. Ennis' run was like a hyper-black comedy at points, and it's over-the-top in terms of violence and malevolence of the bad guys. For fuck's sake, one villain digs up Frank's dead family to piss on them on camera and then sends that tape to all the news organizations. It's just really really evil folk that you want Frank to dismember and maim.
Other than that, the last run I read basically describes why Frank as a figure is adopted by police organizations. That's the run where Frank goes to L.A., makes friends with a police officer who shoots a fleeing criminal in the back, and, when confronted by her superiors about that, calls him a "thug." I swear to god, someone here pointed out a post which better points out the sins of that run, but this Reddit post kinda sums it up.
The way he wrote it, he took this practice of white conservatives who believe that the "war on crime" is actually a war and that maybe Frank has the right idea (seriously, there are a few SWAT teams who have the Punisher skull as part of their patch) and played it completely straight. Suddenly, we had cops and special force guys in the comic that we're supposed to sympathize with looking at the carnage Frank leaves behind and going "Yeah, maybe he's got a good point".
And then the Last Days arc goes full on batshit airport novel with its Burly Action Man Kills Brown Terrorists nonplot.
It's the idea that all criminals are innately evil and deserve to die and want to kill and rape and murder your lineage. It's the idea that you, as a police officer, are the thin blue line separating the civilized society from the criminal animal. Frank, in those writers' hands, becomes a hero in that regard for doing what needs to be done, but Frank is not that.
Frank's a psychotic mass murderer who kills bad people because that's all he can do. He's not a hero but he's not a villain, because he tries to save. That's what Greg Rucka's run is all about, Frank realizing his path is not the right path for Rachel Cole-Alves to follow.
EDIT:
Here's the article and here's the panel: