FH Furr says I need to replace my HVAC system? Fact check needed.

Had an FH Furr tech come out the see if our system needs to be cleaned since it has been awhile. He checked everything over and no said the York 4 burner Furnace (2002) and American Standard 3.5 AC (2014) needs to be replaced.

The furnace has some corrosion around the heat exchanger exhaust (pictured). Is this bad?

The tech said the AC fins were too dirty to and would require an acid wash to clean ($800) but recommended replacing 🤨. (Pictured) can I just pressure wash this out?

The quote is the last picture 🤣.