Comment by CamouflagedKiwi

I don't agree. Domain-specific expertise is valuable (even essential) but can be learned, and usually rather more easily than learning to become an expert software engineer.

I've worked in a number of almost completely disparate domains over my career, each one needed maybe a year or so to become reasonably knowledgeable on, but it's not the same as resetting back to a complete software novice each time.

Also, the people who have been deeply embedded into a domain for a long time tend to overestimate how much it takes. I've seen exactly this with your example of financial software; yes there is domain knowledge but the clear industry lesson has been that it's far easier for software engineers to learn that than for the domain experts to learn software engineering.