[Author of the site here]
It seems we're actually in agreement here :)
You say that any option will be social engineered, and then you go on to explain an option that Apple has already implemented that you don't believe is susceptible to social engineering.
Grandma could theoretically install AltStore, and then proceed to install malicious apps from unknown sources, right now, if she really wanted to. But she won't, because it's too complicated.
I'm not asking for an easy way to sideload. I wouldn't mind if it was made even more difficult than it is now, in fact. All I want is an officially-supported option to do so that isn't prohibitively expensive. An example I provided on the website is Google's ChromeOS. They make it difficult enough to enable developer mode that it's practically invulnerable to social engineering attacks. It's much more difficult to enable sideloading on a Chromebook than it is on an iOS device.
> If you are dead set on it just mentally map in your head the price of a 1000$ device to 1100$ and be done with it
No, it's $100/yr, every year into the foreseeable future, and the cost could change at any time without prior notice. If you stop paying, your apps will stop working, so if you've grown attached to and have become dependent upon your sideloaded apps, it's quite unlikely you'll stop paying.
The Apple Developer Program is not intended as an option to enable sideloading on your device, and it never was. Apple only wants you signing up if you plan on submitting apps to the App Store, which is a benefit you're completely missing out on if you use it exclusively for sideloading.
> "if you really care about it, you can do it" is a fair state of affairs
I would 100% agree, if that were an accurate description of reality, but unfortunately it's not. If you can't afford $100/yr, then no, you cannot do it. It doesn't matter how much technical knowledge you have; you simply cannot do it.
> (I am a bit exaggerating the point but just because it seems like almost everyone is on the other side of the argument)
You and I must not be reading the same website? There is a very large anti-sideloading presence here on Hacker News. Most of it is based on strawman arguments and flawed assumptions, but it's there, and surfaces on almost every thread discussing the topic.