The linked article is essentially correct, but it obscures a couple of important points.

The first is that no Republican, President or otherwise, can change the superedelegate system, because it's peculiar to the Democratic party. In place since the '80s, its purpose is frankly to preserve the influence of party leaders - the superdelegates. These include all current Democrats in Congress, plus local leaders.

The superdelegates aren't *assigned* to vote for anyone. They can vote for whomever they like. If Mrs. Clinton or Mr. Sanders "has" a certain number of superdelegates, that only means that they've already expressed a preference for one candidate or the other. They can change their preferences for any reason - though they usually don't. Recall too that there are many fewer superdelegates than "pledged delegates," whose votes must reflect voter preferences

But the larger point is that there's no requirement in the Constitution for primary elections. These began in the 19th century but didn't take on present-day proportions till after WWII.

Some states assign pledged delegates in proportion to the popular vote. Others are winner-take-all, depending on the rules of the state party apparatus.

In other words, Democrats and Republicans can run their primaries however their party leaders want - or conduct none at all. Before the days of primary elections, all candidates were chosen by party bosses - without much regard (or poll-based knowledge of) whom the voters would prefer. Primaries evolved to reform this system.

The primary system cannot (I believe) be abolished or restructured by any Presidential or Congressional action without violating the First Amendment, which protects political parties from government interference. I suppose superdelegates and the like might be abolished by Constitutional amendment, but no party in Congress would sacrifice its autonomy by approving such an amendment, which would tend to undermine the First anyway.

If the Democrats decide the superdelegate system should go, they alone can make it happen.

The general election, of course, has to be conducted according to federal law: one standard for any and all parties. This includes the electoral college, but that's another, even more complicated, story.

One might consider the whole nominating process "corrupt." Or one might see it as the product of 200 years of unavoidable, pragmatic compromises.