Looking at it as "right" or "wrong" is silly.
You either like the product enough to pay for it or you don't. I believe it's the publisher's job to create a product that offers enough that paying for it feels good.
Of course, for some people paying for something they can get free is just never going to happen, but I think also many people who pirate would pay if they felt they were getting enough for their dollar.
The reality of things is that piracy is so easy and corporations so unimaginably massive that it's basically impossible for the average person to see anything wrong with it. You steal from a store, you have to be there with another human being and know you're depriving them of something. You pirate, you're copying something from a faceless corporation who makes more money in a day than you'll make in a year. Nobody bats an eye these days if you pirate and mp3 or a movie, basically everyone under the age of 50 does it regularly.
Yet streaming services like Netflix and Spotify have greatly curbed piracy by giving you a product that's BETTER than piracy.
So while it's probably not a moral right to pirate, it's hard to see a real logical flaw with it, and hard to have any care for companies that already treat us like statistics. If Marvel and DC don't want people to pirate, maybe they should work on making it so you get more by paying than you do pirating.
Pirating self-published comics is kind of whack though, pretty much the equivalent of going to a mom and pop video shop, looking around and having a conversation with the owner about a film, then when they ask if you'd like to buy it at a discount, you go "nah, I'm just gonna torrent it at home"