That's one issue right there. The market seems to focus on a limited number of models that the consensus says is best, and naturally those models become expensive
General aviation is not dying, it is slowly shrinking. The peak years for airplane production were the late 70's, and the last time the industry produced a reasonably large number of airplanes was the early 80s. The peak year for the number of private pilots was also around 1980, and it has been shrinking since. Despite there being more than 23,000 new private certs earned last year, the number of private pilots shrank by 2500. That's a combination of attrition and career pilot hopefuls graduating up. Airline transport is the only rating that has seen consistent growth over the last 10 years.
In the FAA airmen stats, there is a page where they break down the pilot population by age and rating. The age group with the most number of private ticket holders? 60 to 64, with 19,499, next largest is 55-59 with 17,630. The third largest group? 20-24, with 17,201. The smallest group that is over 20 and under 70 is 45-49 with 11,534. So you have an aging boomer group that will be replaced with a smaller population over the next 10-15 years.
There are two issues that will negatively affect GA over the next 20 years: the tendency for better paying jobs to be in a limited number of metropolitan areas, leading to high real estate prices and competition for space at a limited number of airports, and low aircraft production numbers that consist disproportionately of trainers and SR22s. It certainly doesn't help that Textron does not seem to have any interest in building owner operated airplanes
From what I've read on these pages with the difficulty people have buying airplanes, I have to think they are selling.