IoT and embedded computing isn't a niche market. Most households have more embedded and mobile devices than they have desktop/laptop computers.

It's a variant of their development board for their AI accelerator ship for embedded setups (think quality control, licence plate detector, analysing visitors via webcam etc). This variant is probably just to make it more attractive for hobbyists; increasing mindshare and community size. It doesn't need a huge market, and maybe people come up with cool ideas nobody has thought of yet.