Dennis, I think a lot of this comes down to the type of design you're talking about. Design is a huge field! Visual, UX, CX, graphic, research, front-end, etc.

I would guess that purely visual design is the type of work that's more often perceived as an optional luxury. This dates back to the old days of crappy software that was designed by developers - and it showed because it was very difficult to use! Even though we now credit designers with elevating software to the effortless, intuitive experience we expect, it's hard for some people to shake off the idea that design is still less important than engineering.

Just to play devil's advocate... I do a lot of what would commonly be described as "product design". It's a complex and valuable mix of UX and UI design with some IA, business strategy, system design, copywriting, art direction, critical thinking, problem-solving, and other skills mixed in. It's been a long long time since I worked with a client who didn't highly value my skills. I haven't had trouble getting paid for anything for at least 10 years.

Perhaps the lesson is: if you want to be a designer, find the the fields of design that have the most perceived value. If what you really want to be is an artists, then be prepared to live with the stigma that your work just doesn't hold value to some people.