I would argue against this. Here's my reasoning. Most of those EZ's were finished more than 20 years ago. Say, pre-2000, often pre-1990. The builder was probably a 40 or 50 something guy, sometimes older, sometimes younger, but in the last 25 years, yesterday's 45 to 55 year old became a 70 year old and sold the airplane. The next owner flew it for 5 years and parked it when the first big maintenance event happened, intending to fix it, but the airplane sat in the back of the hangar for 5 years and everything that worked when it was parked doesn't anymore. So now, the airplane needs new everything - paint, engine, avionics, etc, and it takes someone with a lot of money, desire, and ability to bring the airplane back from the nearly dead. There aren't that many guys who wanna do that, so all of those older homebuilts are waiting to be sold for a handful of pennies on the dollar by an estate one day and ended up being salvaged for the engine and re-usable hardware like wheels and brakes.
I know of several nice glass homebuilts around here that were unintentionally retired kind of like this by the owner or the subsequent buyer.