You know, I think part of the angst (all sides and in between) going on right now is that game design is finally moving firmly into the realm of mature design. That means that some parts of the functioning thing are, for most practical purposes, opaque to the user. At its far end, you get the #2 pencil--usable by a mature 4 year old, but unmakeable by any single being on the planet. (We are a long way from that. We've just finally started down that road.

)
It is the difference between, say, a 1967 Mustang or early '70 VW Beetle versus any modern car. Someone interested in motors and willing to work could pretty much maintain about everything in one of those early version that they could physically handle. Lifting the engine out might for a complete rebuild might have pushed it, but I'm sure a few managed even that. Nowadays, you've practically got to be a specialist, and even so, there are some pieces that you'd really rather not touch.
And in not a few game systems for a long time, being willing to get under the hood was more or less the price required to participate, in some ways. Unless you wanted your game to spend a lot of times on blocks, out in front of your house ... (oops, analogy started to run away with me.)
There were people who didn't like Armor as AC, from the very beginning. There still are. But there are very few that play D&D for any length of time, think about it some, but still don't understand why it is the way it is. And most of them are bloody obtuse.
We are starting to hit an era of design where you can use something
without understanding it, and it will just work. The huge problem, of course, is that then when it breaks, you'll have to spend that much more time understanding it to get it fixed--or you'll have to get someone else to fix it for you.