Why do cybercriminals favor using such obscure and complex domain names for their illicit activities?

Cybercriminals use obscure domain names like this because they are less likely to be recognized by users, less likely to be pre-emptively blacklisted by security solutions, and harder to associate with a specific entity. They can be registered quickly, used for a brief period to conduct attacks, and then abandoned, making them difficult to track, investigate, and take down by law enforcement or security researchers.