The Amiga platform is more than 1/4 century old, it is an antique hobby for collectors.
No, of course it's not. First: Amigas are modern computers from early in the modern computer era. Second: Many people who have Amigas aren't collectors. People use the systems to play games, for example. Some people use them as their main machines.
The machines from the '80s and '90s aren't antiques at all, and some of those prices are completely ridiculous.