What kills that board (and many like it) is the absolutely proprietary SYZYGY connector, which is surface-mount (so hobbyists won't develop a board ecosystem for it, and aliexpress circuit cloners won't do their thing unless there's a proven ecosystem), and probably $10 in high quantities (if it's even in stock). RIP.

I'm not even sure that board has enough overall I/O to connect a VGA output, controller inputs, and a SDRAM chip (all of which are essential to a viable MiSTer replacement - note that no one has figured out how to use DDR RAM for emulation yet, too much seek latency).