I've been into Amigas since before Commodore went bust. It's always been an expensive hobby. Back in the 90s, I subsribed to Amiga World and drooled over all the hardware I couldn't afford. I pretty much have all of it these days for, given the general high prices for prime used Amiga gear, much less than I would have paid in the 90s. Of course, it's outdated technology but it still has it's charm and I find it kind of funny that there is still so much interest in it. Nothing comparable in the Mac and PC world.
Back in the day, the Mac was an even more expensive platform but the used Mac Quadras aren't worth anything like an what an A4000 is. The Amiga actually had the low end 500s, 600s and 1200s for the masses. Apple wasn't interested in low end products and all the kids who played with low end Amigas became the adults who fueled the ongoing passion for the Amiga.
Producing new hardware for an old platform is a labor of love more than anything else. The tools to make the hardware are much cheaper these days but it's still a lot of investment for a small return. Specialized electronics with small production runs is always an expensive proposition. It's not just Amigas. There is actually quite a bit of it out there in the world. One of my jobs is maintaining an electronic card control system that is a very specialized piece of hardware with several hundred in existance at most. Original price was around $15,000. Two spare modules were purchased last year for around $1500 because the company no longer produces or supports this product.