Such a version exists as by some modders — but it's buggy and looks like a PS1 game.

: Many "highly compressed" links are clickbait designed to deliver spyware, trojans, or adware to your device. Missing Data

It sounds like a myth, but it’s possible. Here is how "highly compressed" versions bring Los Santos to your pocket without killing your data plan. 🚀 The Magic of 50MB

While tools like ZArchiver can reduce file sizes for easier sharing, compressing a multi-gigabyte game down to 50MB (a 98% reduction) is generally impossible without removing nearly all game assets (like sounds, cutscenes, and high-quality textures).

If a version is truly that small, it is likely a "Graphics Mod" only (which requires the original game to be already installed) rather than the game itself. Compatibility Issues:

: These sites often bundle "bloatware" or unwanted software instead of the actual game files. Legitimate Game Features