Could this type of political organization be considered a "cartel"

Yes, political scientists, economists, and legal scholars explicitly use the term "political cartel" (or the cartel party thesis) to describe this exact type of behavior.

While we usually think of cartels in business—like oil companies or drug syndicates colluding to fix prices and lock out competitors—the exact same logic applies here. Instead of fixing prices, political actors collude to fix the political market and lock out democratic competition.

Why the Comparison Fits Perfectly

• Collusion Over Competition: In a healthy democracy or a free market, actors are supposed to compete. When faction-aligned candidates secretly agree on who will run and who will drop out, or when a judge and a governor coordinate a retirement to hand over a seat, they are replacing open competition with a backroom deal.
• Barriers to Entry: Business cartels create artificial barriers to prevent new businesses from entering the market. By using the "resign-and-appoint" loophole, political insiders create a massive barrier to entry for independent or outside judicial candidates who cannot afford to run against a state-backed incumbent.
• Limiting Consumer (Voter) Choice: A business cartel forces consumers to buy from them at an inflated price because there are no alternatives. A political cartel forces voters to accept a pre-selected candidate because the mechanisms of choice—like an open primary or a fair election—have been intentionally dismantled or bypassed.

The "Cartel Party" Theory

In political science, the Cartel Party Thesis (introduced by scholars Richard Katz and Peter Mair) argues that modern political parties increasingly operate like cartels. Instead of serving as a bridge between the citizens and the government, parties use the resources and loopholes of the state to protect themselves from outsiders, ensure their own survival, and share power among a small group of elites.