You know what discourages users from delving more deeply into the developer side?
For one thing, pages like this:
'A WordPress user does not need to learn PHP in order to use, run, or manage a WordPress powered website.
Most users can use WordPress without ever learning to program or code in PHP."
Yes, on the official WP Beginner page. And it isn't true, as I know now, after several days and dozens of hours of total misery trying to figure out a problem on my site. I finally did, but no thanks to all of the advice out there that consistently says a WP site owner doesn't really need to know anything complicated.
Then, let's take a look at Wordpress: The Missing Manual, by Matthew Mcdonald. (2013) The blurb on the front cover is: "The Missing Manual series is simply the most intelligent and usable series of guidebooks." (Kevin Kelly) Wouldn't you think this would seem to imply that if it isn't in this book, you don't need to know it? (And the other books in that series come a whole lot closer to fitting that description.)
545 pages long, I have read it again and again and again, and I know how to do everything that is in it. But that's not enough, not that you'd ever guess from reading this book or using other sources like it.
The book covers:
Starting out, installation, maintaining the site, building the blog, creating posts, permalinks, WP themes, widgets, theme customizer, using pictures, posting excerpts, adding pages and menus, making WP look like a website, comments, plugins, gravatars, mobile support, backing up the site, galleries, embeds, shortcodes, embedding video, audio files, podcasts, multiple authors, promotion, sharing buttons, publicizing, feeds, search engine, site stats, editing themes, child themes, adding e-commerce.
Number of times that PHP is even mentioned in this book: 4
Number of times that mysql is even mentioned (and the reader is specifically told that if they have something like a one-click install option, they shouldn't even learn anything about it because they'll never need it): 2
Number of times that FTP is even mentioned: 1
Number of times that scripts are even mentioned: 0 (yes, zero)
All mentions are extremely brief, almost all less than one paragraph, and almost nothing is explained in anything resembling detail.
None of that was any help at all when I ran into the registration problem with my site.
People should not be blamed for not understanding that they really do need to know more than the user side when they run a WP site. That is what most available sources say (that you don't really need to know too much), and it's just wrong. The fact that the "unofficial manual" clearly is making that incorrect statement... it really sums the problem up. Maybe that's the whole story with the OP's issues; maybe it isn't, but either way, the point needs to be made a lot more often than I've ever seen it expressed.