I think this is overlooking the larger issue: in these scenarios there are powerful groups that plan to turn the country into a dictatorship, and that's really

I think this is overlooking the larger issue: in these scenarios there are powerful groups that plan to turn the country into a dictatorship, and that's really the bit to worry about. You cannot simply write down a law prohibiting becoming a dictatorship and then sit back thinking all will be fine, because then these groups will simply grow their power until they can ignore the bits of the law they don't like. And they don't need to change the law to gain power, they merely need acceptance of their telling of events. On the other hand, without extensive support you cannot create a dictatorship because that word implies such extensive societal control that there simply must be extensive power behind it for it to function at all.