Except a huge number of people only ever use reddit on mobile. There are no ad blockers that can target specific advertisements inside of an app itself. You can do network wide advertisement blocking with things like pihole, but the people using reddit on mobile aren’t the people setting up a network wide domain filter. I only ever used reddit on the desktop through old.reddit.com, but I could see the writing on the wall that they’re going to get rid of that sooner rather than later.