If users complain after sideloading was enabled, the Geniuses can simply tap on the sign.
After some taking the customer allowed us to take a look at things before we did the refund. It turned out her nephew, whom she had turned to for help setting up her new computer decided for her that she didn’t need a mac, she needed a mac running windows. He had resized the Mac OS partition to as small as it would go, installed windows and configured boot camp to boot entirely into windows. As a result all the problems she’d had under windows remained (made worse by not having antivirus because “macs don’t need antivirus”) and she never got any of the firmware updates because Mac OS was never booted and never checked the update servers.
Boot camp was an involved process at the time, with plenty of scary warnings and no official support at all. But the end user never even saw them because the “tech” person in their lives just set it up anyway.
The result of this was a few hours of employee time and and out of policy assurance of return long after the normal return policy if the customer still wasn’t happy trying the proper Mac and Mac OS experience for a while.
No amount of disclaimers, not taking responsibility or sign tapping would have gotten a better response, and not taking that responsibility even though Apple explicitly disclaimed responsibility would have resulted in brand damage, costs in terms of returns and restocking and the loss of future sales that (later happy) customer represented.
In the end, customers aren’t impressed with your signs and disclaimers. If apple is the product vendor, they will demand apple fixes it.
At some point you're just going to have to expect users to grow and learn alongside the platform.
Edit: I should also note that Apple is perfectly fine with taking credit, as product vendor, for content that they are hosting on one of their apps, but not actually producing:
https://news.ycombinator.com/item?id=30191126
https://apps.apple.com/us/app/apple-podcasts/id525463029
2nd Edit:
> No amount of disclaimers, not taking responsibility or sign tapping
I've also wondered about that. Apple is a master of UX patterns. The whole green vs. blue message bubbles alone has become a social/cultural signifier. Let's say the UX was similarly tweaked if a user had sideloading enabled, maybe an unsightly header. If there were similar color filters or distinguishing UI that specified installed apps as not from the App Store. Wouldn't that be enough to create user behavior to distinguish between "official" App Store apps and sideloaded ones? Emergent behavior will arise from simple prodding. The green/blue division is real.
Denying service to a lot of users still means having to talk to them. And will leave users upset.
> you make it very visible in the UX that you are essentially in a "non-safe mode" (the actual security status probably varies, but Apple would probably go out of its way to hype up the potential of danger here), and you consent to all sorts of disclaimers disavowing Apple's responsibility here, and recommending they make backups before doing so. In fact maybe they could distinguish between pre- and post-sideloading enablement backups.
Also making security better, like sandboxing all sideloaded apps. But then you are suggesting that Apple takes a lot of time and effort to implement a way for them to lose revenue AND have upset users when their phones are bricked? Even though I want sideloaded apps, I can see why they don't want to do that