As a Kia owner, I’ve never heard of a annual coolant flush. None of the service appointments have had that. Similiar to the poster below, I recall the manual recommending something about the coolant flush every few years or X amount of miles (maybe 60k or so off the cuff).
The past 4 years, the regular maintenance has been tire rotation and their full check and fluid top off. Tire rotation has been around 17 bucks every 7k miles or so.
My extended warranty has paid for itself as there were some failures in parts that have cost more than what I paid for the extended warranty. The service techs have been way more laid back about the warranty than the sales person. I figure the real reason is the manufactures need better maintenance data and how the cars wear over time.
disappointed. thought your hot take was worker wages need to rise.