As for the accessibility of the ideas, they are presented clearly. Where jargon can't be avoided, it is presented by the role it plays, and a simple explanation of what it is not (see the digital signature panels) that presents an idea, gives the user enough information that they can start forming a question and addresses an incredibly common misconception.
As for being in a minority, I don't know. What I do know is that as a person who has to deal with dyslexia on a daily basis in a largely text based position as a remote security engineer, I found this content to be very approachable, and it got positive feedback from several folks I shared it with this morning, including an early childhood educator and a retired teacher, so YMMV.
As far as not being the target audience, frankly, I am squarely in the target audience as I am always looking for new and effective ways to teach people this stuff because as an infosec weenie a big chunk of my job is helping people avoiding the pitfalls of technology by helping others understand how to build secure or maintain basic opsec. This comic is not effective for me, since I am technical enough to need better resources, but it is super great for a project manager who might need to ramp up knowledge about why HTTPS or TLS is important without needed to know how to configure or implement it.
They clearly aren't. Some users already pointed out they had problems getting what the cat was supposed to represent. That's a telltale sign of how bad the content was presented when a significant portion of the audience, and one which is educated and technically inclined, has a problem understanding and tracking the meaning of a basic concept that's presented right in the very start.
People aren't "reading it wrong". The comic is simply poorly thought-out and the execution makes it needlessly hard to go around these problems.
If you think it's fine, I wager it's for one of two reasons:
- You may have decided it's fine because you're ignoring the issues by dismissing them as "it's because I'm not the target audience".
- You may actually be in a minority of people who have no issues reading this.
Put it this way, if I print content in light-grey on a pastel-white background and have people complaining about this, I shouldn't be defending it with "Oh it's not fine for you, but for other people it's fine". That's the whole challenge of accessibility: Making your content accessible to the biggest chunk of your target audience (and if possible, beyond that).