Mini game consoles are cheaper to build, so they can be sold for $60-100 and more like the SNES Mini Classic which cost $80. A lot of people are more likely to buy a mini console which they can afford instead of borrowing money to buy a more expensive gaming tablet which cost more. A good gaming tablet like the Nintendo Switch, Razer Edge tablet, Nvidia Shield tablet, and Wikipad, or a faster regular tablet like the iPad and Microsoft Surface Pro can cost $300-1000 depending on how expensive the screen cost, and how much the other parts like controller, CPU, RAM, and speakers cost. Fewer people can afford a gaming tablet, so they maybe less popular. There are also probably more people who rather play popular game categories like shooters and RPG games on a TV than a smaller tablet. I think there will always be companies like Nvidia, Nintendo and Sony making mini consoles like the Shield TV, SNES mini, and Playstation TV to sell to people with less money or just want a cheap mini console. There are also a lot of people who use mini consoles to play older console emulators, and retro games on Android, Linux, and Windows based mini consoles. But, there are probably fewer people who regularly play game console emulators, and retro games on a small screen device like a laptop, tablet, or small TV.