"The person's qualifications and achievements will be largely taken into consideration, together with their loyalty to the Party, who their parents are, friends in high places who vouched for them, favors that need to be returned, etc... Not that much different from the capitalism."

Bingo.

At a macro level ideology has little to nothing to do with policy decisions compared to protecting the power of those who are already empowered/priveleged.

... which is par for the course given human history really.