The current “system”, more accurately a non-system, is a travesty.
It attempts to bridge two completely incompatible concepts or frameworks for how the end result should be achieved.
First (and quite respectable) is that each major party (both private organizations composed of paid and volunteer staff) should appoint delegates and convene every four years and that said convention, using reason and debate, should freely choose the nominees most likely to serve their interests (usually winning).
Second, and kind of novel, is the idea that (some) voters should choose the nominee, either by plurality or majority voting.
The attempt to meld these two opposing concepts into a smoothly-functioning system is a failure.
The biggest problem with the primary system is that there are no consistent qualifications for voting, and, worse, the qualifications to vote are not set by the parties but by the states in which the primaries are held. A primary system is under the control of often hostile state election bureaucracies rather than under the control of the parties.
Our free republic was built on states rights. As a strong supporter of the 10th Amendment, and equally strong advocate for repealing the 17th Amendment, I am satisfied with the current delegate selection process that leans heavily on states.
The problem today is corruption, incompetence, and cronyism in Washington DC, not the sovereign states. I therefore don’t want republican elites in DC dictating primary rules to the states.
Be careful what you wish for.