OK, the warning could perhaps be better designed. But I still don't see the huge problem: "Trusted" has a very strong meaning when used for any computing devi

OK, the warning could perhaps be better designed. But I still don't see the huge problem: "Trusted" has a very strong meaning when used for any computing device. So this is already a really, really strong warning sign (safeguard 1). Next, you explicitly have to go to the settings to manually trust the certificate (safeguard 2). This gives you a lot of time (i.e. you don't accidentally "click/touch OK") to inform yourself intensively of the consequences of the decision (safeguard 3). Even after that according to this link (no screenshot is shown), you explicitly have to confirm your decision again (safeguard 4). Now according to this link, you have to install the apps from the now-trusted developer manually (safeguard 5). So I see at least 5 levels of safeguards that Apple introduced.