The Master System never took off in the US, barely even considered an competitor to the NES given its dominance. Instead, Americans were given the Game Gear, and most people never realized it was basically just a Master System with an LCD screen slapped inside of it (and an adapter was released to play Master System titles on the portable).
It was sort of a revelation at the time, that bright, glowing color screen miles ahead of anything Nintendo was doing on the portable front. That said, it didn’t have Tetris, and the Game Gear’s killer app was Sonic. Unlike Tetris where early LCD tech could afford to smear, playing a speedy platformer doesn’t work as well.
So, the Game Gear had to excel elsewhere, although Sega did release a plethora of Sonic titles for the system anyway (including the oft overlooked Tails Adventure). The downgraded ports of popular Genesis titles could do quite well for themselves actually, Streets of Rage 2 excelling in terms of its gameplay. Slower platformers like the sluggish but still enjoyable Shinobi scored too, also featuring a stunning soundtrack, a rarity for anything on the limited sound hardware. There were hidden gems, stuff you would never even think to consider on a meager handheld like Fatal Fury Special and Samurai Shodown. Fantastic ports that work within the limitations.
Of course, playing the thing these days practically requires an AC adapter since the battery life is so awful and any rechargeable battery packs are long dead. The hardware is also meeting an untimely end in many cases with fading screens due to failing capacitors inside the casing. It’s fixable, but many will probably find it a lost cause.
The Game Gear will live on as a Virtual Console addition, or you could always just pick up a Master System.