In what universe did Clinton beat her opponent? She won the popular vote which means nothing, that's not the system they use. She would have beaten her opponent if she actually campaigned in the states that mattered instead of being lazy and taking voters for granted. She was either lazy or didn't want to go because it would have been too much for her, she might have collapsed would have had to have been held upright by campaign aides during her visits.
If we ignore the post I replied to, about the British popular vote, and pretend we're discussing the US Presidency you may perhaps be right about all that American detail about how Clinton played their "rigged" system worst and got Donny his job.
Since we are not discussing that stuff, but a very rare plebiscite and following events in a country that operates by an entirely different system, I didn't read those details closely won't argue them as they have no relevance across the two votes.
The popular vote in both Britain and the US does compare in almost every aspect. On that head-count Clinton beat her opponent by a percentage quite comparable to the Brexit 'majority'. If such minor percentages were sufficient to settle things and persuade the half of the population hating the result that they should move on to other concerns, neither country would be roiling in acrimony now. Another way of stating the point about Brexit I offered above.
If all you wanted to say was that the US vote winner campaigned as ineptly as the UK vote loser, I've said it for you. So what? When such small margins mean winning is indistinguishable from losing in its power to settle the question at issue and enable progress, it bolsters my point.