You're arguing two things.
1. Is the system rigged, and setup to enable the party orgs. Absolutely. Should it be changed. Absolutely.
2. But that's not what all of you are saying, you're saying that despite him overcoming the challenges of being an outsider to win the Republican nomination. Despite him winning the electoral college when facing a conglomerate of media that were not only actively campaigning for Hillary, but were passing debate questions and strategizing with her election team....that despite him winning inside that corrupt and unjust system. The mere fact, the system is broken and rigged is being used to de-legitimize him.
Yes, the system is rigged, broken, and corrupt. Winning in spite of all that is damn impressive. But if you're going to say the fact that said system is broken makes Trump's election illegitimate. Than it would have also made Hillary's win illegitimate, and all of our recent presidents were illegitimate. In which case, your barking about only one election winner is rather hypocritical. Thus, your argument for Trump's illegitimacy and removal is null.